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Author Topic: CAt vs Cummins for my next rig - diesel pusher  (Read 55445 times)

joester

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CAt vs Cummins for my next rig - diesel pusher
« on: October 16, 2006, 02:11:43 PM »
I thought I'd post a new question I have after talking to my mechanic.
without posting what he told me, I thought I'd ask owners of each and what they have experienced.
I'm looking for a short (32-34) diesel pusher, and so far really like the Holiday Rambler Neptune pbd,which is basically the same as the Monaco Cayman.
I believe these come with the Cummins ISB 300 hp engine.
what are your experiences with these rigs and more particularly this engine.
thanks so much.
any info on rigs with a similar CAT engine would be great help to me - and what makes use the CAT engines?
tener corazón de oro

1991 Tioga class C

Chet18013

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #1 on: October 16, 2006, 06:07:49 PM »
Both are good engines. I have a CAT in the motorhome and have a Cummins in my truck.  I would not hesitate to have either one , or even a Detroit, in our next MH--that is if we ever wear out the one we have.

Chet18013
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Tom

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #2 on: October 16, 2006, 06:33:12 PM »
Like Chet, I wouldn't hesitate to have either one. We have a Cummins in our coach and a pair of big CATs in our boat. We have forum members with both makes in their respective motorhome and I don't recall hearing or reading any dissatisfaction with either one.

We had an issue when both CATs broke turbo studs while we were at sea, but we were able to get home safely and CAT went out of their way to take care of the repair and cover collateral damage.

A friend and forum member recently had to be towed when his new coach with an ISX Cummins engine broke down one day out of the factory and the nearest Cummins dealer/tech couldn't fix it. But the problem was resolved promptly by Cummins once they were towed to a knowledgeable facility.
« Last Edit: October 16, 2006, 08:36:03 PM by Tom »
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BernieD

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #3 on: October 16, 2006, 06:45:36 PM »
Joe

I have had both a CAT and a Cummins engines in my 2 coaches. Both were/are fine engines. I do question the ISB engine in a full sized Class A coach. Everyone that I know that has that engine in a coach has been disappointed. Major problem is low torque, about 600#/ft IIRC.
Bernie & Marlene Dobrin
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Tom

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #4 on: October 16, 2006, 06:50:14 PM »
I do question the ISB engine in a full sized Class A coach.

Bernie, I was about to do the same, but realized he's talking about a "short" (32-34 foot) coach. It would be good to know the weight of that coach.
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Smoky

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #5 on: October 16, 2006, 08:30:59 PM »
I have a Cummins 330 in my coach and I have been very pleased with it.

Originally, when I first started shopping for a coach i only looked at those with Caterpillar.  All my life I had admired Caterpillar equipment and thought it was the premier diesel.

But then I became attracted to Newmar motorcoaches.  I was disappointed that the current Newmar offering in the 2005 year was all Cummins.  I did some research and the more i researched the more I liked what I saw.  We had our first visit to a Cummins shop in Bakersfiled California and were VERY impressed with them.
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Jackliz

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #6 on: October 16, 2006, 09:09:32 PM »
I thought I'd post a new question I have after talking to my mechanic.
without posting what he told me, I thought I'd ask owners of each and what they have experienced.
I'm looking for a short (32-34) diesel pusher, and so far really like the Holiday Rambler Neptune pbd,which is basically the same as the Monaco Cayman.
I believe these come with the Cummins ISB 300 hp engine.
what are your experiences with these rigs and more particularly this engine.
thanks so much.


Detroit first, then a Cummins.

Jack and Liz
Blue Bird Wanderlodge with 500 HP Detroit Diesel, 8V92

Regards,
Jack and Liz Pearce and Oreo the Escape Cat
Fulltiming in a 1993 Wanderlodge WB 40 ft
Dhanis, TX - Winter
Buena Vista, CO - Summer

blueblood

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #7 on: October 17, 2006, 09:05:49 AM »
Joe

I have had both a CAT and a Cummins engines in my 2 coaches. Both were/are fine engines. I do question the ISB engine in a full sized Class A coach. Everyone that I know that has that engine in a coach has been disappointed. Major problem is low torque, about 600#/ft IIRC.

Bernie _ I and a lot of my friends had the ISB275/300 in FW Discovery at ~24,000 GVW and liked them very much. We got close to 10-11 MPG and could clear mountains at 35-45 MPH. In fact a close friend of mine has a trailer with his Corvette in it and has had good performance across US and up to Alaska. Torque is a contant 660 ft lbs across the entire operating RPM so it gives better performance than some engines with advertised higher peak torques at RPM that are not in operating range.
« Last Edit: October 17, 2006, 09:08:08 AM by blueblood »
Leo

BernieD

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #8 on: October 17, 2006, 11:35:34 AM »
Bernie _ I and a lot of my friends had the ISB275/300 in FW Discovery at ~24,000 GVW and liked them very much. We got close to 10-11 MPG and could clear mountains at 35-45 MPH. In fact a close friend of mine has a trailer with his Corvette in it and has had good performance across US and up to Alaska. Torque is a contant 660 ft lbs across the entire operating RPM so it gives better performance than some engines with advertised higher peak torques at RPM that are not in operating range.

Leo

I am glad that you are having good results with your ISB. My comments were based on friends that have/had coaches with the ISB engine.
Bernie & Marlene Dobrin
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joester

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #9 on: October 17, 2006, 11:40:46 AM »
thanks for all the replies.
my mechanic mentioned that he had not worked on the most recent Cummins engines, but the earlier (pre-2003) engines he had worked on were not made as well as the CAT's he had worked on. I'll pass on the info on the Cummins you have shared, and ask him to ask around with other mechanics as to the newer engines.
I did notice the torque on the Cummins is about 660, whereas the CAT 350 hp says that it has 860 - 200 ft/lbs of torque seems to be a big difference.
the Holiday and Monaco I like are about 25k lbs empty - probably 32k lbs loaded - is the 300 hp with 660 ft'lbs torque enough for me to climb thru the rockies with no trouble?
what about with a car or trailer in tow?
I appreciate the help - when I do finally make the step up, we will be keeping it for quite a while, so I want to be sure to ask all the questions now.
thanks for all your input.
tener corazón de oro

1991 Tioga class C

CurtRR

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #10 on: October 17, 2006, 02:53:32 PM »
Different size engines, but I noticed that Country Coach, in their new Tribute 260, charge extra for a 400 hp. Cummins over a 400 hp. Cat.
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BernieD

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #11 on: October 17, 2006, 05:24:33 PM »
Different size engines, but I noticed that Country Coach, in their new Tribute 260, charge extra for a 400 hp. Cummins over a 400 hp. Cat.

The Cummins ISL 400 has 1200 #/ft of torque, I believe the CAT only has 1050. Also, the ISL 400 probably includes an engine compression brake (similar to but with a different name and design as the Jake Brake), while the CAT probably includes an exhaust brake. The exhaust brake works well but not as well as the engine brake.
Bernie & Marlene Dobrin
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Missing our Travel Supreme

Tom

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #12 on: October 17, 2006, 06:12:04 PM »
Bernie,

CAT has an option for the Jake brake, but I don't know which engines do/don't have the option and it may not be offered as an option on some coaches with CAT engines.

The CAT engines in our boat have provision for Jake brakes, but they wouldn't do much for slowing the boat down  ;D
« Last Edit: October 17, 2006, 06:19:16 PM by Tom »
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BernieD

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #13 on: October 17, 2006, 07:34:33 PM »

CAT has an option for the Jake brake, but I don't know which engines do/don't have the option and it may not be offered as an option on some coaches with CAT engines.


Tom

True there is an option but unless the coach builder decides to order his chassis from the chassis builder with that option when he places his oriiginal order and specs, it will be either very expensive or very long delivery time or both.
Bernie & Marlene Dobrin
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Terry A. Brewer

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #14 on: October 17, 2006, 08:58:21 PM »
Tom

Cat C-10's and above have 3 stage jake brakes....at least at Country Coach.


joester

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #15 on: January 21, 2008, 03:20:24 PM »
resurrecting this thread I started a while back - still considering the plusses/minuses for each of these -
say compare a 300-325 ISB Cummins with a 325 CAT - years 2005-2007.
any further input for me? I still like the 32pbd Cayman/Neptunes, but am more open now to a 34'.
I've added the Fleetwood Expedition to my list of potential rigs - saw a 2005 34h I like - I believe it has the 325 CAT. I like the 3 slides so much more than the 2 - the living area gets so much bigger when open.
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Mblaster

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #16 on: January 21, 2008, 09:44:09 PM »
Do the fleetwoods that you are looking at have rear or side radiators?
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BernieD

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #17 on: January 21, 2008, 10:28:47 PM »
resurrecting this thread I started a while back - still considering the plusses/minuses for each of these -
say compare a 300-325 ISB Cummins with a 325 CAT - years 2005-2007.

Both are excellent, fairly bullet proof engines. Not sure about the specs for those years, but generally, the CAT torque figure was significantly higher than that of the ISB. With a choice of the two, I'd take the CAT.
Bernie & Marlene Dobrin
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Ron

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #18 on: January 22, 2008, 08:10:21 AM »
Based on the way Cummins reacted t the problem on some of their ISL engines of installing an idiot light warning that the engine is about to come apart I vote for the Cat.  We do have a Cummins but I sure wouldn't buy another from a company that  installs an idiot light instead of ficing a manufacturing defect. JMHO.
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joester

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #19 on: January 22, 2008, 08:29:06 AM »
have not looked THAT close on the Fleetwood Expedition to see where radiator location is - but really like the floorplan with the 3 slides - the living area opens up nicely.
as to the Cummins, not sure if the ISL is that similar to the ISB that are in the  32pbd Cayman/Neptune I like so much.
I can see where torque difference would make a difference, but in a 32pbd - wouldn't 660# be sufficient?
I'm still not so sure I want to go 34', but like I said, the floorplan and the CAT make the newer fleetwood 34h a nice rig to consider.
thanks for the input.
tener corazón de oro

1991 Tioga class C

Gary RV_Wizard

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #20 on: January 22, 2008, 08:38:51 AM »
The smaller engines and lower end rigs generally have rear radiators rather than side.  Side rads cost more and use up some bay space, so they tend to appear only on larger and higher end rigs.

As for Cummins vs Cat, I would ignore that factor in choosing a rig.  They are both excellent and service is widely available for both.
Gary
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Ron

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #21 on: January 22, 2008, 08:48:14 AM »
I have lost confidence in Cummins.  I know the big problem I mentioned occured on ISL engines but based on the Cummins recall and fix of installing a warning light to let the driver know that failure will occur shortly rather than fixing the manufacturing defect I would wonder what they would do if a new engine had a manufacturing defect.  Things can and do happen during manufacture.  But the ONLY proper way to fix a manufacturing defect is to fix it not install a warning light.  For me we have had our last MH powered by Cummins.  JMHO
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Tom

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #22 on: January 22, 2008, 10:29:58 AM »
I wouldn't be so quick to criticize Cummins; At least they made customers aware of a potential issue. We have the other brand in our boat and had to limp home when both engines broke studs holding the turbos. The resulting mess wasn't pretty - air filters clogged, engines sucked the filters down, soot bypassed the squished filters, and every square inch of the engines, transmissions and engine room was covered in black, oily soot. Had to dismantle the salon to raise the decks so the techs could remove the blocked aftercoolers and replace the broken turbo studs.

There had been a "service bulletin" issued to dealers with a specific instruction "do not replace until failure occurs". I read it when a tech inadvertently left it on the boat. The engine manufacturer paid for almost all the cleanup, salon teardown, and repair work, for which I was grateful. Fortunately, we were relatively close to shore, nearing the end of a journey up the CA coast. But, had we been 20 miles offshore in bad weather, that could have been a lot more serious than it was. Had I been notified of a potential problem, I would have had the simple replacement of studs done before we left home.
« Last Edit: January 22, 2008, 10:31:43 AM by Tom »
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Ron

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #23 on: January 22, 2008, 10:43:31 AM »
IMHO Cummins should have been required to fix the manufacturing defect that could lead to the engine dumping its guts out all over the highway which could very well be a safety issue.  It sure would not give sombody any comfort to know they have a light that will illuminate letting them know their engine is about to sprew its insides all over the road.  What if this happend on a bridge or anywhere that there was not room to pull over.  Very good potentional for an accident IMHO.   Like I said when I heard of the Cummins fix I lost ALL confidence in them.  IMHO Cummins should have fixed the internal manufacturing defect insted of expecting their affected customers to worry if and when their warning light would illuminate.
« Last Edit: January 22, 2008, 10:47:10 AM by Ron »
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Tom

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #24 on: January 22, 2008, 10:54:15 AM »
Understood Ron, but at least they were warned the engine might fail and had the option to stay home. I'd much prefer to break down on a highway bridge than 20 miles offshore in bad weather.

On the first leg of the same trip, we had to head for the nearest port of refuge when the weather forecast was dead wrong. I found myself having to make a wide U-turn in 20'+ seas, heading to a strange harbor while dodging reefs and praying we wouldn't capsize. Had we lost power at that point, we would have been in a world of trouble.
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Ron

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #25 on: January 22, 2008, 11:05:41 AM »
Understood Ron, but at least they were warned the engine might fail and had the option to stay home. I'd much prefer to break down on a highway bridge than 20 miles offshore in bad weather.

About that option do you know anybody that bought a motorhome to stay home.  I don't really consider that a good option.  IMHO The ONLY proper way to address that issue would have been for Cummins to fix their manufacturing defect.  I know that the defective part was supplied by to Cummins by one of their vendors but surely Cummins should be inspecting the components they are installing on a new engine.
Quote
On the first leg of the same trip, we had to head for the nearest port of refuge when the weather forecast was dead wrong. I found myself having to make a wide U-turn in 20'+ seas, heading to a strange harbor while dodging reefs and praying we wouldn't capsize. Had we lost power at that point, we would have been in a world of trouble.
 

Glad you didn't have engine failure at that critical time. 

How comfortable would you feel taking the boat out if it had a pair of the affected Cummins ISL engines and Cummins had fixed the problem by installing an idiot light?
« Last Edit: January 22, 2008, 11:08:06 AM by Ron »
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Tom

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #26 on: January 22, 2008, 11:22:49 AM »
Based on the two stories, which engine would you have in your next coach? I'd much prefer to be told and be able to make the decision to leave or stay home than unwittingly put lives in jeopardy because I didn't know there was a potential issue. One of my worst fears is drowning.
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Ron

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #27 on: January 22, 2008, 11:33:43 AM »
Let me put it this way would you buy a brand new coach knowing that the engine has a manufacturing defect as some of the ISL?  Probably not.  Now would you buy a used coach if it had an idiot light installed to warn you that the engine is about to fail because the engine has a manufacturing defect?  Also probably not.
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Tom

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #28 on: January 22, 2008, 12:15:54 PM »
Maybe I wouldn't buy either next time around Ron, but that does limit the options. Personally, despite the two stories, I believe both brands of engine are OK and, given some of the alternatives, are good value. I might think twice about buying a coach having the 'known bad' engine, but wouldn't rule out other engines from the same manufacturer.

OTOH I'm not planning on buying another coach or another boat. We're quite happy with the ones we have  ;D
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Ron

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #29 on: January 22, 2008, 12:22:53 PM »
We are not planning on buying another coach for the same reason.  However, I have told American coach that I will not even consider a new coach with a Cummins engine.  Interesting I am not the only one that feels this way.
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Tom

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #30 on: January 22, 2008, 12:53:59 PM »
Back to the original question ... All other factors being equal, if choice of engine is the only thing left, the one factor that might weigh heavier in the equation would be torque. HP is a derived number (IIRC we have an explanation in the library).
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blueblood

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #31 on: January 22, 2008, 06:14:34 PM »
IMHO Cummins should have been required to fix the manufacturing defect that could lead to the engine dumping its guts out all over the highway which could very well be a safety issue.  It sure would not give sombody any comfort to know they have a light that will illuminate letting them know their engine is about to sprew its insides all over the road.  What if this happend on a bridge or anywhere that there was not room to pull over.  Very good potentional for an accident IMHO.   Like I said when I heard of the Cummins fix I lost ALL confidence in them.  IMHO Cummins should have fixed the internal manufacturing defect insted of expecting their affected customers to worry if and when their warning light would illuminate.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------


Rod failures are not uncommon and thus this particular manufacturing defect went undetected for some time as it was simply seen a a random occurrance . However, once investigation showed it was part of a pattern Cummins did a review to determine the best way to approach the problem taking into account any possible safety issues and the impact on customers as well as usual cost issues. The defect rate was forecast and likely failure scenario.  In addition, it was found during the review that an existing sensor planned for 2007 engines could be used to accurately predict this type of pending failure.   

This defect was forecast based upon statistical data to affect about 60 RV engines and most were expected to be early failures on way to dealers i.e. maybe 25+ would be delivered to customers. Cummins put in place a process to assure that the affected customers on longer mileage vehicles got quick service and from comments I have seen on many forums and reviewed with Cummins it was well executed and received.  The so-called idiot light is really just the end indication of a quite smart software program running in the ECM and one benefit of having it installed is that it will find out whether the engine is having the problem before it goes to a major failure thus turning a possible 2-3 week repair into a 2-3 day one. In fact, in one instance I am aware of, when after installation of the sensor the engine was started and it immediately showed a defect allowing the problem to be corrected right then. Historical actual data to date shows the defect rate is below the forecast  and the sensor did allow a number of customers to get to repair place before the major failure occurred.   I have an ISL400 not within the affected range but I did have the sensor installed. As I noted before, rod failures are not uncommon in any engine builder i.e. they do happen for a number of reasons and I therefore saw a benefit to having it for added information JIC.

The information I am reporting here is my understanding from talking to Cummins personnel but may be in error and certainly does not represent Cummins position per se.   
Leo

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #32 on: January 22, 2008, 10:08:42 PM »
Let me put it this way would you buy a brand new coach knowing that the engine has a manufacturing defect as some of the ISL?  Probably not.  Now would you buy a used coach if it had an idiot light installed to warn you that the engine is about to fail because the engine has a manufacturing defect?  Also probably not.

Ron

The coaches in question have neither of the issues involved with the installed engines. It is a non-factor.
Bernie & Marlene Dobrin
Home is Goodyear, AZ
Missing our Travel Supreme

joester

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #33 on: January 23, 2008, 08:10:32 AM »
so now my next question would be, how similar is the ISB 300 I'm considering to this ISL?
do they have the same problem?
I'm not too familiar with the differences between the different Cummins engines.
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Ron

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #34 on: January 23, 2008, 09:10:02 AM »
so now my next question would be, how similar is the ISB 300 I'm considering to this ISL?
do they have the same problem?
I'm not too familiar with the differences between the different Cummins engines.

No the problem mentioned was only on some ILS engines.  My concern is how Cummins addressed the factory defect. 
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Gary RV_Wizard

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #35 on: January 23, 2008, 09:11:33 AM »
Completely different engine, even a different block.

I have no concern at  for the 8.9L ISL in my 2004 coach. As Leo explained, very, very few engines will ever experience the failure or even the idiot light warning of it.
Gary
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joester

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #36 on: January 23, 2008, 09:57:35 AM »
I think I have come up with what I think is a fair assumption - as far as a shorter coach - 32-34' DP -
the difference between the CAT and Cummins ISB is not really enough in the 300-325 hp range where it alone should be a deciding factor, correct? It seems that in the 2005-2006 years we're looking at, CAT seems to have more torque than the Cummins ISB for comparable size engines, but most everyone who has either of these engiines is pretty satisfied.
thanks again for your input -
Joe
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judway

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #37 on: January 23, 2008, 10:06:27 AM »
If you are interested in getting a good idea of how horsepower and torque relate I suggest you look at this

Wayne
« Last Edit: January 23, 2008, 11:55:49 PM by Tom »
Judy & Wayne
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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #38 on: January 26, 2008, 03:24:54 PM »
Wayne
 
I understand everything you wrote, but there is one situation where torque is king and that is if you ask the question what is the steepest hill I can go up in my lowest gear? That is determined by the torque peak.

Bob

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #39 on: January 26, 2008, 03:50:42 PM »
Bob

I did not write the article. I just referenced it to look at. My basic opinion is with proper gearing, there is no difference in getting 300HP from a gas engine, a diesel engine or an electric motor. The horsepower delivered to the drive wheels is what does the job. The gear ratio is just as important.

Wayne
Judy & Wayne
2003 Itasca Horizon 36LD
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Remco Towbar, Demco Baseplate & Air Force One Brake
1995 GMC Sierra Z71
No Dogs!      No Cats!
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golfndog

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #40 on: August 05, 2008, 09:17:41 AM »
Joester, If you are still looking for a Neptune.....here it is.

http://omaha.craigslist.org/rvs/783500032.html

Todd Anderson
402.578.7776
Todd

joester

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #41 on: August 05, 2008, 09:37:02 AM »
thanks -
we are staying put with our class C for as long as we can.
until we retire, we're going to fly longer distances, and only use the rv
for shorter (under 600 miles) trips. we'll still use it for trips to Mexico, SoCal, Las Vegas,
White mt's and all, but for longer trips, we decided to fly and maximize our vacation days.
thanks again for the link.
tener corazón de oro

1991 Tioga class C

Ken & Sheila

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #42 on: August 06, 2008, 10:23:25 PM »
The newest version of the C9 CAT (with 9.4L vs the old 8.8L) has up to 425HP (like the Cummins) and up 1350FT LBS torque (vs the 1200 for the ISL Cummins).
The CAT used with an Allison transmission is limited to 1250FT LBS, but with the new CAT transmission it is 1350.

ken
Ken & Sheila
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JerArdra

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #43 on: August 07, 2008, 12:45:44 PM »
If I were buying today (I'm not) I would go Cummins because CAT has said they would no longer supply engines to the MH industry after, I think, 2010.  I know they will supply parts but they probably will not develop a network of special service facilities like Cummins is doing.

RE Detroit Diesel:  They have told Prevost Coach that they will no longer supply Detroits to them.  Prevost is teaming with Volvo Diesel for the future.

The word I hear is that it is because they, CAT or Detroit, cannot meet the new soon-to-come pollution standards for diesels.  The MH industry may be in deep DO-DO if Cummins can't.

JerryF
JerryF  ;D  ;D

carson

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #44 on: August 07, 2008, 01:07:12 PM »
Sounds to me like the "Greenies" are still making progress. Maybe it is time to get some "gutsy" politicians elected.
(This is carson and I approve this message)  ;D

carson FL


Carson, 
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Ex RV'er. (1995 Winnebago Adventurer)
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...Logic works like a charm...

Tom

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #45 on: August 07, 2008, 01:32:48 PM »
Might be time to consider Man diesels. Their web site says that their tradition"goes back to Rudolf Diesel, who developed and built the first completely serviceable diesel engine in the world between 1893 and 1897 at MAN".   Be prepared to pay a high premium if you specify one of their engines.
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Ron

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #46 on: August 07, 2008, 01:52:29 PM »
With the Allison Transmission being such an excellent transmission I wonder why anybody would want to take a chance on an unknown Cat transission until it has proven its reliability and worth.
Ron & Sam-home is where we park it. Currently located   HERE

carson

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #47 on: August 07, 2008, 02:18:32 PM »
Speaking about VOLVO engines...

   I don't have much knowledge about their product line (yet).

I had a 6 cylinder Volvo in my 35' Chien Hwa trawler some time ago. Worked fine but did not last. I replaced it with a new Perkins. Mechanics told me that the VOLVO was too 'lightweight' for that application.

  Luckily I had the boat chartered out at the time and the Insurance paid for it. Sold the boat shortly thereafter.

FWIW,  carson FL

Carson, 
 West Central Florida
Ex RV'er. (1995 Winnebago Adventurer)
2007 Buick Rendezvous, SUV / CROSSOVER

...Logic works like a charm...

Tom

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #48 on: August 07, 2008, 02:42:41 PM »
Volvo engines are in many long-haul Volvo trucks.
« Last Edit: August 07, 2008, 02:44:25 PM by Tom »
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carson

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #49 on: August 07, 2008, 03:11:47 PM »
I am certain that VOLVO is a fine product.

Tom, wonder if you saw the 'alternative fuel' article on the Volvo website.

Check it out here

Carson, 
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Ex RV'er. (1995 Winnebago Adventurer)
2007 Buick Rendezvous, SUV / CROSSOVER

...Logic works like a charm...

Tom

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #50 on: August 07, 2008, 03:52:59 PM »
Saw the link, and intended to come back and read it. Thanks for the reminder.
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jrshall

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #51 on: January 21, 2010, 06:32:27 PM »
Do the fleetwoods that you are looking at have rear or side radiators?

I wanted to ressurect this thread, especially this question.

I am looking at a 2005 HR Neptune with the Cummins and rear radiator. Is there a problem with the rear radiator setup? If so, are there any solutions?

Thanks, Jerry

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #52 on: January 21, 2010, 06:48:12 PM »
I am looking at a 2005 HR Neptune with the Cummins and rear radiator. Is there a problem with the rear radiator setup? If so, are there any solutions?

Jerry

The only solution is to look for a different coach. Rear radiator models are cheaper to build so are less expensive. Side radiator coaches provide more usable space in a given length coach and can generally run cooler. Rear radiators have a tendency to spray a coating from the oil vent tube on the air cooler causing overheating problems. Newer and better rear radiators have thermostatically controlled fans, the older ones were direct drive and always on, taking a 30-50 hp constant toll.
Bernie & Marlene Dobrin
Home is Goodyear, AZ
Missing our Travel Supreme

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #53 on: January 22, 2010, 09:41:42 AM »
Based on the way Cummins reacted t the problem on some of their ISL engines of installing an idiot light warning that the engine is about to come apart I vote for the Cat.  We do have a Cummins but I sure wouldn't buy another from a company that  installs an idiot light instead of ficing a manufacturing defect. JMHO.

my mh has is on a xcr freightliner chassis with a ISB 6.7 cummins..it has an analog oil pressure gauge and a low oil pressure warning light and buzzer ;)
peter d

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #54 on: January 22, 2010, 10:19:26 AM »
We have a 35' 2003 DP with a Cat rear radiator, and have been all over the place; up and down 13-14% grades in eastern Canada with over 75,000 miles on the odometer .  It's been a great engine. 

My feeling on the Cat vs Cummins debate is everything is so computerized now; that it really doesn't matter which one you get.  If you like the floor plan of the coach and everything else, then don't worry about the engine.

Marsha~
2017 Heartland Mallard IDM231 Travel Trailer....Small but mighty.

jrshall

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #55 on: January 22, 2010, 10:57:16 AM »
Rear radiators have a tendency to spray a coating from the oil vent tube on the air cooler causing overheating problems. Newer and better rear radiators have thermostatically controlled fans, the older ones were direct drive and always on, taking a 30-50 hp constant toll.

Can the vent tube be rerouted? Does that also spray onto the toad? How would I tell if the fan is always on? Would it free wheel if I try to spin it, with the engine off of course? The one I'm looking at has a Cummins ISB in a 2005 HR Neptune.

Jerry

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #56 on: January 22, 2010, 12:16:06 PM »
There are various solutions to the oil breather tube problem, including extending it or attaching a catch bottle, but the biggest cause of oil spray is overfilling of the engine when changing oil.  The dipsticks are installed by the coach manufacturer and are not always marked correctly for the engine capacity.
-- Ned -- Fulltimer 1997-2013
1997 Holiday Rambler Endeavor LE
2007 GMC Canyon

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #57 on: January 22, 2010, 10:09:51 PM »
Can the vent tube be rerouted? Does that also spray onto the toad? How would I tell if the fan is always on? Would it free wheel if I try to spin it, with the engine off of course? The one I'm looking at has a Cummins ISB in a 2005 HR Neptune.

Jerry

As Ned indicated, there are reroute choices. Spraying the toad has been know to happen but can be resolved by not overfilling the oil or by rerouting. You may be able to get an answer from HR. Monaco owners on the forum may have contact info.
Bernie & Marlene Dobrin
Home is Goodyear, AZ
Missing our Travel Supreme

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #58 on: January 23, 2010, 11:17:18 AM »
To tell if our fan controller was working correctly you started the engine cold, ran the engine up to 1000RPM, and checked to see if the fan was turning.

In our case, with a controller, it should NOT be turning.

tennsmith

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #59 on: January 24, 2010, 01:57:01 PM »
I have a Cat 300 in my 36 1/2' Itasca Horizon.  So far, I am totally satisfied with it.  We don't pull a toad as of yet and it seems to have awesome torque to pull the long grades.  Mileage is close to 10.  The exhaust brake implementation on my Cat involves the transmission as well and forces a transmission downshift in combination with exhaust restriction.
Bob Smith
Huntsville, AL
2000 Itasca Horizon 36LD
300 Cat
6 speed Allison

crackodawn

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #60 on: February 01, 2010, 09:34:25 PM »
Bernie, I was about to do the same, but realized he's talking about a "short" (32-34 foot) coach. It would be good to know the weight of that coach.

My 34' Journey with a 350 HP ISB is never wanting for power. Granted that might be seen as a full sized coach but it goes up hills and pulls faster than I need to go and is legal in most states.
Only the prepared survive, all others perish.

Jessie

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #61 on: February 10, 2014, 01:39:46 AM »
We are not planning on buying another coach for the same reason.  However, I have told American coach that I will not even consider a new coach with a Cummins engine.  Interesting I am not the only one that feels this way.

My husband and I been searching for just the right motorhome for us and he is dead set on another Cummins. I have NO PROBLEM with that. His 1992 Dodge 1 ton dually fully loaded up and truckin' with a Cummins engine still purrs with no signs of slowing down anytime soon. Interesting we are not the only ones that feel that way ;)

driftless shifter

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #62 on: February 10, 2014, 07:09:30 AM »
I drive semis for work. Cat and Cummins, both stout engines. I have found a Cummins to be a smoother running, quieter engine.
 Horsepower is how fast you can hit the wall, torque is how far you can push it.

Bill
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I'm an analog guy in a digital age.

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #63 on: February 10, 2014, 10:10:30 AM »
The OP is looking at a 32 to 34 ft. coach. He mentions 2 different Monaco products. He did not state if he was buying new or used. Cat left the MH business in 08 as they could not meet the EPA standards. The few 07's with the Cat C7 are horrible engines with lots of pollution equipment problems. The DPF plugs constantly and cat never provided a fix. Posters should realize that very few MH's that short are either rear rad or large engines. Foretravel and maybe one other had an ISL but they are rare and expensive. The rest are all entry level. Not all Cats are great nor are all Cummins great. It depends on the year and model. Most entry level MH's went to the Cat C7 in 05. They are all rear rad. The Cat is very powerful and does have better fuel economy. BUT they do have 2 serious problems. They use an HEUI fuel injection system and the pumps are prone to failure. Even at miles as low as 30,000. Very expensive fix. About $7000.00. The fan bearings go and cause a lot of damage. About $1500 or more to fix if the rad survives. The Cummins small block is a good engine. They never had that rod problem but in 200 or 2001 they had head problems. later models are fine. The Cat spews oil out the puke tube . That can be fixed by extending the slobber tube but the rads still need to be cleaned every year. We have owned a Cummins in a 02 Bounder and currently have the C7 in an 05 Bounder 34 ft. The OP should be aware that some Monaco's have problems with the trailing arms. There are fixes but you should allow for that fix in your offer price. Other Monaco's have some serious handling problems in the short lengths if they are on a Roadmaster. Fleetwood and Winnie use a Freightliner chassis and it handles well. But do realize that no short DP will not handle like a 40 ft. DP.

Marsha/CA

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #64 on: February 10, 2014, 11:03:56 AM »
Please note, this thread is 6 years old, I'm sure the OP has made his decision by now.

Marsha
2017 Heartland Mallard IDM231 Travel Trailer....Small but mighty.

moisheh

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #65 on: February 10, 2014, 11:46:38 AM »
Marsha:  I am embarrassed! I just saw it in new threads and posted away!!

Marsha/CA

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #66 on: February 10, 2014, 12:25:55 PM »
moisheh, don't be embarrassed....it happens all the time.  People do a search for information and then miss that it's a bit old. 

However your info was interesting.  We have a Cat in a 2003 coach and love it.  It's a 3126 which is a C7 or the forerunner for a C7, I never did find out which one.  We have the oil changed at 6,000 miles and do an oil analysis; always trying to stay ahead of things.

Marsha~
2017 Heartland Mallard IDM231 Travel Trailer....Small but mighty.

BigRBlueS

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #67 on: February 10, 2014, 08:19:55 PM »
I've never had a Cummins, but echo the praise for Big CATs in the boat!

I've got a 7.3 International (a little more difficult to find in RVs outside Icon and Gulfstream Super Cs) in my '02 Ford that has been built proof pulling my 37' 5er and anything else I have put behind it!
  Banks kit, 300,000+ miles, and NO repairs needed! I'm knocking on wood!
Carriage Cameo 37RE3
'02 Ford F350 Dually

oldme

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #68 on: February 17, 2014, 04:20:47 PM »
This may be an old thread, however I find the information very interesting.
It helped me meet my personal objective of learning something
new everyday.

Thanks for everyone that shared their knowledge.

rbigwheels

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #69 on: February 21, 2014, 12:46:09 PM »
We are Full Time RV'ers & we have only owned one Diesel Pusher Motorhome...It's a 1997 Safari, 35' w/a CAT 3126 300hp engine & exhaust brake. We have 70k miles on the coach & we love it. I have it serviced every year @ the CAT Dealer in Redmond, OR & so far there have been NO major problem. We tow a 2005 Jeep Liberty, loaded w/2 kayaks & 2 bicycles. We get 9mpg and are able to climb most hills in 4th gear @ 45-50mph. The exhaust brake is fantastic & when going downhill, I often have to keep my foot on the accelerator to keep from slowing down too much. We travel w/friend (sometimes) who have Cummins Engines in similar coaches & they love their coaches. I believe either a CAT or Cummins Engine would be Great, as long as they are maintained according to the manufacturers recommendations...  :)

TonyDtorch

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #70 on: February 25, 2014, 10:36:30 AM »
We are not planning on buying another coach for the same reason.  However, I have told American coach that I will not even consider a new coach with a Cummins engine.  Interesting I am not the only one that feels this way.

Fleetwood may want to may re-think that decision,  the choices left are Cummins,  Volvo, Maxxforce or Mercedes.
But Cat is no longer making highway engines....

« Last Edit: February 25, 2014, 11:13:06 AM by TonyDtorch »

joester

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Re: CAt vs Cummins for my next rig - diesel pusher
« Reply #71 on: March 10, 2014, 02:49:24 PM »
OP here - still driving and loving our 1991 Tioga class C, and still looking ahead for whatever it is we buy next might be. Interesting that it was almost 8 years ago I posted that - and I still don't know what we may end up next. fwiw - we have 37 months to retirement, and plan on keeping our class C as long as possible. A year ago we replaced the EPDM rubber roof, and just before that added a full set of Michelins.
Still runs like a champ, passed emissions Saturday with flying colors. Still love that rv and glad we shopped all year in 1997 to find it. I did see a 2005 Holiday Neptune recently for just over 50k - looked to be in nice condition, so I may just end up with one of those down the road. I'll revive the thread if we do!
for now, it's spring training Cactus League and tailgating on weekends, then pretty soon it'll be time to head to the pines for trout and cool weather.
tener corazón de oro

1991 Tioga class C