Does a 500 HP Cummins DP cost more to service/upkeep than more common 300+ HP

I occasionally see a MH with this large of an engine and am wondering if the service/upkeep on them is much more costly?  Might that large size be over kill?  Anyone have experience with these larger Cummins engines.

Our first diesel motorhome was a 34-feet Monaco Windsor DP with a Cummins 350 hp engine.  We loved it!  This engine also was used in larger 40-foot motorhomes and I suspect the extra weight would make them a little less spry than ours but certainly adequate in most circumstances.  Incidentally, the decision to upgrade from gas to diesel was made as we were going up I-70 toward Eisenhower Tunnel which is over 11,000 feet in elevation.  As we were chugging along in our Chevy 454 and being passed by lots of diesel rigs, Jerry said "I want a diesel pusher."  We found the Windsor the following year.  Yes, it was more expensive than a gas engine.  Jerry changed the oil and lubed it a couple of times but we don't recall how much oil it took.  We eventually moved up to our current Monaco Executive DP which is 40 feet in length, weighs under 40,000 pounds, and has a Cummins 500 hp engine and, guess what, we love it even more!  Jerry did the maintenance on it once and it took (without going back into our records) about 40 quarts of oil.  We use synthetic oil and that costs more than the regular oil.  The oil filter is quite a bit larger, about 7 inches in diameter and maybe 1.5 feet in height.  If you change your own oil you have to have a really large container to drain the old oil into and then a way to disperse/funnel it into smaller containers that can be recycled.  Our recycling trucks have oil reservoirs and we spread it out over a couple of weeks so they're not overwhelmed.

We've reached a point in life where Jerry doesn't want to do all that anymore so we pay to have someone else do it.  We were lucky to find a guy who comes to the house and changes the oil and lubes the Zerk fittings.  I think the only other two big things were that the charge air cooler had to be replaced and the closed plastic container that holds the radiator coolant had to be replaced.  The charge air cooler was still under warranty so we were lucky it didn't cost anything but time.  Jerry ordered the coolant container and replaced that himself.  If we're traveling and need to have any service like an oil change we find the nearest Cummins dealer.  We passed 102,000 miles last summer and it's still running beautifully.

I guess the best way to put it is that as you move up to heavier engines there will be more cost in terms of maintenance.  But that might be offset by other factors such as liking the ability to move heavier rigs up mountains.

ArdraF

SissyBoyFloyd said:

I occasionally see a MH with this large of an engine and am wondering if the service/upkeep on them is much more costly?  Might that large size be over kill?  Anyone have experience with these larger Cummins engines.

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I have yet to hear anyone complain about having too much horse power in their RV - even regarding the maintenance expenses. Too little horse power... now that's a different story.

Kev

Might that large size be over kill? 

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Not likely in a coach with one installed. I had a Beaver with a 525 HP CAT, and it didn't accelerate or climb hills quite as well as my Ventana with a 360 HP Cummins. Of course the difference between 50,000 lbs and 36,000 lbs might have something to do with that. Upkeep might cost a little more, since everything is bigger, and it holds more oil, but it probably isn't as big a difference as between gas and diesel.

I believe our 2007 Cummins ISB, 350 HP, only requires 4 gal of oil. Also I think it does not have sleeves, so the coolant may not need as much attention. Our coach weighs less than 26,000 and with the Allison 3000 6 speed, we have never had any problems. Of course, we have always pulled a honda, which helps.

SissyBoyFloyd said:

I occasionally see a MH with this large of an engine and am wondering if the service/upkeep on them is much more costly?  Might that large size be over kill?  Anyone have experience with these larger Cummins engines.

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I'd assume that most of the big trucks you see by the thousands have the larger Cummins engines...  I'd also assume that if the routine maintenance were a big difference they would not buy 'em...  OTOH, if they fail, I'd expect the big ones to cost way more to replace or repair plus they cost way more to buy initially.  For most RVs, it seems to be handy and great for big mountains or cruising the interstates at 75 mph but a smaller engine will get you there... maybe an hour later though.

Diesel engine "size" is a fooler,, many engines can be basically the same but be various "sizes" (250 275 300 325 350 etc.) the cost of individual parts are based on design more than size as many parts are use commonly on several "sizes".>>>Dan

How often do you change the oil in a DP?  Is this the only routine maintenance required for DP's?  I have never owned one but am going that route when I am ready to purchase a RV

The engine, transmission, chassis are all relative to weight.  If it has a 500hp, it probably needs it.

Speedco pricing isn't based on engine size, so I would say general service (oil - filters) doesn't make a difference which DP you have, they cost the same.

ON top of the oil filter, there can be 2 fuel filters, 1 very large and expensive air filter, around $100 or more, a hydraulic filter, and a water separator filter. I may be missing a few more as well. There definately is an expense to it.


Bill

One of our former members had a Cummins engine that had to be replaced.  I think it was a 350 hp and I recall that their new engine cost $17,000 and that was about ten years ago.  Now that's a big expense!  And Kevin is correct.  Our big engines may cost more but none of us complain about the horsepower!

ArdraF

billwild said:

ON top of the oil filter, there can be 2 fuel filters, 1 very large and expensive air filter, around $100 or more, a hydraulic filter, and a water separator filter. I may be missing a few more as well. There definately is an expense to it.


Bill

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Ya be he was asking between a 300hp and 500hp and they all have similar filters and costs.  The 500 is no more expensive than the 300.

I have a 600isx. The cost is not much different for smaller engines other then the cost of oil. I have one oil filter and 2 fuel filters. There about 20 bucks each. I change annually so way under the mileage mark .Most work is the same as all engines just checking fluids.