Why are DP's more expensive?

[ahicks]

I think you need to make arrangements to drive one. Much of the necessary justification will be handled at that point. ;^)

The fact the DP chassis are best described as "oversized" as compared to gas means you can carry and tow pretty much anything you want (as long as it will fit!) - something you must pay close attention to when loading up/driving a gasser.

Resale numbers should enter into your decision as well, especially when selling a coach with over 100k on it.

We all know and deal with the struggle getting to the top. What about the ride down? What would the concept of much more worry free trips down be worth to you? The DP exhaust brakes (makes no difference what type) really do take a lot of the worry out of what can often be a pretty frightening experience in a gasser. Between that and the extra braking power available with air brakes makes for much more downhill confidence here. Kind of hard to put a number on that?

[docj]

Originally Posted by oakcreekeric

Keep in mind, they make DP's that are very close to a gas chassis.. see all the entry level DP's out there.. basically (in my opinion) they are nothing more than a gas chassis with a low HP diesel engine.. but when you get into the mid to high end DP's.. you get all the "good stuff".. air-ride, air-brake, engine brake, more HP and bigger transmissions..

This is a point that is often overlooked. Many of the "affordable" new DPs are being powered by small diesels, essentially the same Cummins engine that Dodge puts in pickup trucks. Comparing that 6.7L "baby" diesel to my CAT C-12 or a Cummins ISX is truly like comparing a Kia to a Mercedes.

Yes, you can get a lot of HP out of a small-block diesel if you spool it up, but you can't really change the torque it can deliver. Yes, HP is what gets you up the hills, but torque is what moves you out at a light or on an acceleration ramp of the interstate. Driving a DP powered by a large block diesel is a fun experience. My engine loafs along at ~1200 rpm at highway speeds which is also roughly its torque peak. Climbing mountains barely raises its temperature and it doesn't even know it's towing a vehicle.

I don't know what a new C12 would have cost but I've seen used ones with ~400k miles advertised for ~$6k. Similarly, a friend of mine had to have his Allison 4060 transmission replaced due to a mechanical failure and I think the installed cost for a new one was ~$19k. So you can assume the powertrain alone on a DP with a large block diesel probably cost ~$40k when new. Compare that to some low end DPs that don't cost much more than a couple of times that, in total, and you can begin to understand why the cost of some DPs can be so high.

These days you pretty much don't find ISX-class engines being installed in DPs until you get to the >$500k level. Given the cost of the powertrain it wouldn't make sense to put it in a less expensive coach. Entry level DPs up to the $150-200k level use the 6.7L ISB. With the 8.3L ISC no longer being built, most $200-500k coaches, I think, are using the ISL which is the smallest Cummins engine capable of having a true compression brake.

That's another thing, don't let anyone tell you that an exhaust brake and a compression brake have the same effect. That's another KIA/Mercedes argument and would only be made by someone who's never driven with a compression brake. Nothing beats the secure feeling you have coming down a mountain with the Jake on at maximum and the transmission in 4th (or even 3rd). I've actually found myself, more than once, having to touch the accelerator to avoid slowing down on the downhill!

So to sum it up, DPs are more expensive because their powerplants are more expensive and because there is lots of extra "stuff" installed on them that isn't found on gas MHs. For starters, try finding a gas MH with air suspension; there's no reason why there can't be one, but I doubt you'll find many (any?)

[TQ60]

Ours in on a Gillig chassis.

Some laugh about it being on a school bus chassis but being built in Ca to ca school bus requirements means much higher safety requirements than what would be on a delivery truck frame or general duty mh frame that typical gasser would have.

The frame rails under look like a bridge and the cabinets inside are built with 3/4 solids and plywood for large areas.

The gassers usually have lighter duty chassis which restricts the materials to lighter weight which results in sometimes a cheaper look and feel.

Recent gassers much better than old ones but still corners need to be cut to keep weight down where the dp focus is more on build quality and feel and less on saving a couple pounds by using plastic instead of wood.

Due to larger everything the cost of materials and parts are going yo also be more.

[flynnwalter]

Raining Star
If you plan to purchase a coach around 40', then there really are no gasser choices. Your comment: " Many gassers are every bit as elegant as some DP's." leads me to believe you either prefer a gasser, or really don't understand a pretty big difference exists between the two. Visit some factories and see/learn how gassers and DPs are built. Unless you are looking for a coach in the 35' and under range and a relative lightweight in GCWR, you should research the DPs. Size matters. And then there are always plenty of DPs around that are long on glitz and short on longevity and quality. The learning curve is steep, and after many years I am still learning. I would suggest a used DP coach made by a quality manufacturer. Good luck!

[Old Scout]

Lots of opinion here but think Frank in Florida has said it best. Once you get past the "DP envy" and the "mine is bigger than yours" issues; it comes down to paying for larger/heavier frame and suspension components--engine and tranny add to cost too. There are exceptions to every rule but generally speaking, DP frames are made from truck components, designed for 100,000s of miles or even millions. Most gassers are built with lighter duty components.
However, I tend to view it as a whole package deal. Most gasser builders struggle with sheading weight to meet the capacity limits of their frames/suspension. DP builders have more flexibility so tile, solid wood, and carrying capacity make for a more comfortable experience--my opinion of course. The most evident compromise for a gasser is the limits on the front axle weight and the resulting rear over-hang on the back axle. With the engine and tranny mostly over the front axle, the rest of the coach has to be re-distributed over the back axle.
Bottom-line--dont try to sort our the biases between gasser and DP owners. Do your home work, drive a bunch of both types, then make you own decision based on you personal travel needs and what you have experienced after the test drives. Good luck......

[Steve Ownby]

Originally Posted by Raining Star

I'm not asking if they are worth the extra cost, but trying to learn what factors make them so much more expensive. Is there massively more steel, aluminum, etcetera in a DP engine and frame or what?

While I don't know, I can't imagine the manufacturing process is significantly different than building a gasser.

It's all about size and weight. Gas chassis are limited to about 25-26k pounds. At 40' with slides it becomes a real challenge for coach builders to put together a coach on a gas chassis. The diesels over lap slightly with gas chassis at that weight with the Cummins ISB, the Maxforce 7, or in older coaches the Cat C7 or 3126. Above that weight and with 40' and above coaches it's diesel only. The medium duty ISL is found in many coaches in the 40'-42' range and weight up to mid 30k. Above that, in 42'-45' coaches up to 45-50k pounds the Cummins ISX12 and ISX15 are the overwhelming engine of choice. The Detroit Diesel is starting to be used in a few chassis. Older coaches might have a Cummins ISM or one of the big Cats.

The only coach size with a gas/diesel choice is in that 38-40' range and up to 26k pounds. Below 20k pounds it doesn't make sense to spend the $$$ on a diesel drive train. Above that range, a gas drive train doesn't have the capacity.


Steve Ownby
Full time since '07

[zmotorsports]

Originally Posted by Raining Star

Several people seem to be misunderstanding the original question. I should have asked "why DP chassis are more expensive than gas chassis?"

Obviously everyone understands that a more luxurious motorhome is more expensive than a basic motorhome. That isn't the question.

In a single word, weight. A gas Class A will accomodate many if not all of the same "systems" that are found in a diesel pusher Class A. They all have a domestic water system with a water heater, they all have a furnace, they all have a stove or cooking device. The difference comes into play when the owners/consumers want more and more and nicer and nicer amenities and more living space, ie longer coaches, period.

These higher end cabinets with solid woodwork, solid surface countertops, tile floors, in floor heat, bigger and bigger televisions, residential refrigerators, hydronic heating and the list goes on and on all the while keep increasing the weight of the coach to the point that the chassis as well as the engine/transmission need to be increased to accomodate the weight. This is where the larger chassis comes into the picture with heavy duty Class 8 truck components to support the weight, get the weight moving and more importantly to get the weight stopped safely.

Mike.

[zmotorsports]

I guess I should have read Steve's post above before posting mine. Pretty much stated the same thing.

Mike.

[Tha_Rooster]

Originally Posted by Raining Star

But I know the reason for the price difference in the types of cars. I doubt national labor cost differences is a big factor between a Gasser and a DP.

A DP and a Gasser aren't the same as comparing a BMW and a KIA. Many gassers are every bit as elegant as some DP's.

Your right on elegant looks can be deceiving it's the ride. As a 2 BMW owner I don't think labor cost have anything to do with it. To answer the op's question, the ride most gasser are produced on mass produced truck chassis and DP (mostly) are built on custom Rv chassis.

[Raining Star]

Originally Posted by Tha_Rooster

Your right on elegant looks can be deceiving it's the ride. As a 2 BMW owner I don't think labor cost have anything to do with it. To answer the op's question, the ride most gasser are produced on mass produced truck chassis and DP (mostly) are built on custom Rv chassis.

Many of the DP's I've seen, at least in the price range I'm looking at, are built on the Freightliner truck chassis, and as a professional driver I'm comfortable enough with it having sat on one for twenty years and several hundreds of thousands of miles.

Again, my question most clearly wasn't aimed at comparing RV bodies, I was asking simply about what components of the chassis of a DP accounted for the higher cost. I'm grateful that has been answered by several people here.

I doubt anyone needs to have it explained to them that a very luxurious coach interior is much more expensive than what you get in the particle board economy model. Personally I'm in the process of building a new S&B retirement home, so I'm all too well aquatinted with the price difference between the rosewood cabinets, slate floors, tiled showers etc, that DW ordered over the standard features that were shown in the base price.

[Mr_D]

Originally Posted by Idahoboy

Your question is a good question. But you really need to break it down to two parts.

Part 1 engine, and drive train and frame.
Engine a Diesel engine is designed to run well over a million miles before a major over haul. the engines they run in dp's are usual a very close variant or even the same engine in over the road semi trucks. They are built to last just the engine you can get 40 to 60k into.

I'd dispute that in the case of the Cummins ISX 650 like we have! 45,000 miles and has dropped valves on two different occasions and on it's third turbo.

[stan5711]

When I was looking at motorhomes I had my mind made up I was going with gas and in the 32' range,looked and drove a bunch of them,then a salesman talked me into to driving a DP,38' long,set down in the seat,i was scared to death,that sucker seemed hughes,well I drove it and that's when I knew I hade to have a DP,the drive,the ride,everything was so much better.Now I'm wanting a 42'

[Monacoach]

Some dps drive better then gassers but when parked they are pretty much identical inside .

[GN2ZDGS]

Chassis is way different and air bags are my biggest plus!!