Caterpillar Engine Performance Improvements

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The Historic mileage on this MH has been 6.9 miles per,
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chris, that mpg seems low to me. I know you were pulling truck with MC but I'm wondering if there is something else going on also. I have the 330 cat and when I'm towing an 18' enclosed trlr with two MC & stuff in it I still get over 8 mpg and it is terrible for wind drag. Without towing I'm getting 9 - 91/2 or so. Just giving you a comparison and wondering.
 
We have a 39' Tradewinds towing a Honda CRV and our mileage on a cross country trip will average 8.5 mpg while towing and our total mpg for this year is 8.1 mpg. (Including a lot of east coast city driving). I also believe 6.9 mpg sounds low; could that include the fuel used in the generator?

When I added a Banks system to our last Pace Arrow it improved the performance but out mileage dropped slightly.

Going faster always seems to cost more. :-[
 
Ya know, I was concerned that the fuel mileage was at 6.9 on this rig when we bought it, but didn't realize that it should be better (i'm new to diesel).  I will be getting the Freightliner chassis serviced in a few weeks.  I will see if the guys doing the service can find any reason it might be lower than I am hearing on the Forum.  With diesel fuel cost as high as it is, it sure makes the trips bite the budget.  Gas prices in Albq. have been dropping to as low as $2.94/gal. lately, but in some places diesel seems to going up a bit ($3.68 to $3.84).  I have asked why the big difference and the answers are unacceptable; diesel OTR trucking taxes are higher due to hiway maintenance cost, supply and demand, etc.
It cost less to refine diesel, so it should cost the same of less than gasoline...one would think...!
 
In Abq, today, the low for diesel is 3.35 with 4 more places under 3.50. I use gasbuddy .com. I paid 3.41 at that same station for 80 gal 3 weeks ago. That's how I save $.
 
Hey Bob, thanks for the info.  I will be givin gasbuddy.com a look and I will definitly stay out of Montana...$4.46/gal is making a statement, "do go anywhere in your diesel vehicles"...
 
Here's another useful site for fuel prices, also includes a map: http://autos.msn.com/everyday/gasstations.aspx
 
Tallulah said:
Ya know, I was concerned that the fuel mileage was at 6.9 on this rig when we bought it, but didn't realize that it should be better (i'm new to diesel).  I will be getting the Freightliner chassis serviced in a few weeks.  I will see if the guys doing the service can find any reason it might be lower than I am hearing on the Forum.  With diesel fuel cost as high as it is, it sure makes the trips bite the budget.
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One problem we had involved our side radiator fan. They are hydraulic with an electronic controller that had failed on ours because it had not been relocated properly when our motorhome was built. When the controller fails it runs the fan on high continuously to protect the engine. It uses around 40 hp and cost us about 1 mpg.

If you have a side facing radiator it is easy to check. When the engine is cold start up and see if the fan is running at 1500 RPM or so. If it is the controller has a problem.
 
I will see if the guys doing the service can find any reason it might be lower than I am hearing on the Forum.
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Chris, I don?t know how handy the Freightliner guys might be on the mpg problem. I would suggest starting with you local Cat dealer. Run you serial and arrangement number by them to see if there are any service or warranty records on your HEUI system like injector change, etc. If it was done at a dealer they will know.
Also, the mpg I am using is running in economy mode around 60 to 65 mph. I run most of the time with cruise off because of traffic but do use it when I can. Watch your rpm or speed when you do your mpg test so you can compare apples to apples. Once you have multiple tests confirming your 7.1 I would also try to do some checks not towing anything just to see the difference if that?s possible. This would eliminate any outside influences from the towed vehicle. Sounds like you?ve had the rig a while so I assume your air filter is clean and running below 20? and you?re not having any other issues with smoking etc.
1 or 2 mpg can be gained or lost by lots of things but the most probable cause is usually driving habits. If that?s what it comes down to at least it is an easy fix.
 
Yep, its been awhile since I checked the replies, but thought it important to note that as someone commented...am I forgetting to account for my generator fuel useage..., and YES I was.  I will including that fuel useage in future calculations.  Thanks...!
 
Is Chet still around?  :)  another good site for fuel prices and diesel info is dieselboss.com it lists travel plaza prices and info.
 
Yes, I'm still around. However we got rid of the Beaver with the CAT and propane injection system 5 years ago and now have a Monaco Signature with a Detroit Series 60 engine. I liked the CAT, but this Detroit is an incredible engine and I really prefer it over the CAT.

As for fuel prices, I use the Gas Guru app on my iPhone. It has all the local stations, travel and truck stops with maps.
 
You were moving your Mom I believe way back when!  Glad it worked out so well for you on that coach!
The 60 Series has got the torque for sure..could always use more power!  :)  The semi's with the Detroit's get great fuel economy gains..
Cheers!
 
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