Diesel more sluggish than gas?

[Mostovi]

New to the site, so hello to everyone. Will be moving into the motor home world soon. I had pretty much settled on DP or large super C, but I've read several posts here where some folks said some diesels are actually more sluggish than gas. Contrary to all I've ever heard. Can those of you with more experience than myself please explain? Thanks!

[gutfelt]

Bill.Satellite wrote:
1 post, 1 response. All 6 days ago. End of discussion.

That's your opinion and of course like others here everyone is entitled to their own
I think theres been many good responses that address or attempt to address the OP concerns

[Bill_Satellite]

1 post, 1 response. All 6 days ago. End of discussion.

[Cloud_Dancer]

If you haven't lived through ownership of 5 gasser Class A MHs, each one better than the previous, and all those years been envious of those who drove big diesel pushers (as they passed you on the highway with their engines sounding like they were loafing),.....and THEN ordering a spanking new big diesel pusher equipped just the way you want,....don't eeevven talk to me about gassers being just as good. Well, it's my experience and my opinion. And NOW I feel like a "settler" again,....now I want a new NEWELL! I might have to die a settler's death....:B

[JaxDad]

gutfelt wrote:
there are reasons there are no 40++ diesel pusher style motorhomes with gas engines if it takes a 9 litre 425 HP motor with 1250 lbs torque to move my 36000 DPMH efficiently how would a gas engine ever do that (realistically)

When I was a kid on the farm we had a GMC tandem axle gas powered truck tractor. It had the TwinSix V12 engine, it was a 702 cu. in. that made a whopping 275hp and 630 ft./lb. of torque....... at 1,600 RPM.

Yes, it made its best torque at 1,600 RPM.

It would haul 60k to 80k of potatoes or grain just as well as our diesel powered REO would.

It’s not a matter of what CAN be done, it’s the ‘coffe shop factor’, the guys that buy $80k pickups with big diesel engines as ‘daily drivers’ because they look so good parked out front of the coffee shop on Saturday night.

The same goes with $500k motorhomes, the average someone spending that much doesn’t care about efficiency, economy or durability, it’s bragging rights.

You got it, spend it, no problem.

A buddy of mine just spent $120k on a Tesla X, claims it’s so great because it costs him soooo much less to drive to his weekend place.

Ok, so he ‘saves’ $60 a week for 6 months of the year after spending $120k on a new car.

[Solo]

ScottG wrote:
Diesels dont have that instant response off the line like a fuel injected gas engine. Where they shine is once they get moving a little and in the hills.

Oh boy this has been fun! I enjoy reading the "Ford vs. Chevy vs. Dodge" type responses but, the above very first response to the OP's question pretty well answers the question-especially since the OP was asking about Class A or Super C rigs.

Unless I was forced to for some reason, I don't think that I would ever return to a gas powered Class A motorhome for all of the reasons that other DP owners have already posted.

Count me as "sluggish" if you want but, it is SO much more comfortable traveling in a DP CLass A motorhome.

[tropical36]

Mostovi wrote:
New to the site, so hello to everyone. Will be moving into the motor home world soon. I had pretty much settled on DP or large super C, but I've read several posts here where some folks said some diesels are actually more sluggish than gas. Contrary to all I've ever heard. Can those of you with more experience than myself please explain? Thanks!

Diesels are all about low end torque, not break necking acceleration and It's what you want for pushing heavy equipment. It still amazes me when pulling a 6% grade with the tach at 1400rpm, passing a lot of trucks and not hearing a sound from the engine.

[Gjac]

Diesel vs gas discussions could go on for pages and not reach a definite conclusion because there are so many variables and are not apples to apples comparison. Op I would suggest reading Johnny T's diesel vs gas under frequently asked questions he goes into much detail and you will learn a lot from his Sticky Post. I would start with what size MH to you want. If you want a 40 ft MH to fulltime or travel in get a diesel. If you want a shorter MH to frequent SP's, NP's, or NFS CG's a shorter gas MH would be more appropriate because you will find many more spots where you MH will fit. A 40 ft MH would fit in some NP's but have much fewer spaces that will accommodate them. As far as your performance question if the MH's were the same size, HP and weight I would choose the diesel but that is not the case. DP's usually weight much more for the same HP so it is not a fair comparison. Most of these discussions provide no performance metrics that one can use to determine which MH will perform better, but a simple test is to measure the time it takes to get from 40-60 mph. If folks would post these times,HP and the MH's weight you would have meaningful data to make a decision based on performance. I have tested a number of MHs and have found that lighter gas MH's in the 30-32 ft range will take about 12-14 secs, 33-36 will be about 14-16 secs, several 40 ft DP's I test drove were 17-22 secs. You will find a DP with 330-350 HP that weights 30k lbs or more will have less performance than a 340 or 362 HP gas MH that weights 15k lbs. For a more detailed explanation read Johnny T's Sticky.

[hipower]

gutfelt wrote:
there are reasons there are no 40++ diesel pusher style motorhomes with gas engines if it takes a 9 litre 425 HP motor with 1250 lbs torque to move my 36000 DPMH efficiently how would a gas engine ever do that (realistically)

Gas engines moved loads over twice that weight for years. Quite effectively and efficiently. The key has always been gearing. With the automatic and automated transmissions available today providing more gear ratios than the popular six speeds we currently see is easily accomplished. The technology is already available and being used in truck fleets around the world.

I've always been a bigger is better guy and if I could justify a 600 horse diesel with 1,500 ft lbs of torque, or more, I would love it. But for many RV applications that is serious overkill. Diesel drive trains require more expensive components and maintenance costs from oil changes to nearly all other parts which may be needed. I realize my thinking here is a lot like swimming upstream, but many things in life are like that. If no one bucks the status quo nothing changes. Here limited mileage and generally intermittent use would suggest that my thinking, while outside the box, isn't exactly earth shattering.

[gutfelt]

there are reasons there are no 40++ diesel pusher style motorhomes with gas engines if it takes a 9 litre 425 HP motor with 1250 lbs torque to move my 36000 DPMH efficiently how would a gas engine ever do that (realistically)

[hipower]

Mr.Mark wrote:

hipower wrote:

gutfelt wrote:

hipower wrote:
This has been an interesting discussion and I can only offer my somewhat biased opinion based on many years of heavy vehicle operation as well as many years of RV ownership.

Our current coach is a 2003 Dutch Star with a Cummins ISC 350. It is no race car nor is it quick from a standing start. Does it do what I expect of it? Absolutely, and quite effectively. We have had numerous years where we traveled 10,000 plus miles and regardless of which coach we were driving they all did the job. Currently we are traveling about 2,500 miles per year and from a point of size and investment we could get by with less coach until we park for extended periods of time and the room is more important.

If I had the luxury of designing a coach chassis from scratch based on our use today it would have a 500+ c.i., turbocharged gas engine in a rear mounted configuration. Backed by a 8-10 speed automatic transmission with air ride suspension and air brakes. Obviously such an animal doesn't exist, and the closest thing to what I describe was the recent Workhorse rear engine chassis which had a short life and was overpriced, in my opinion with, very limited numbers of manufacturers offering them in their lineups.

Obviously this diatribe doesn't answer the OP's question, but my take on this whole thing is simple, if acceleration is a major factor in a buying decision maybe motorhomes aren't the best way for someone to travel.

BUT a 500++CID turbo diesel will still out perform your gas idea that's the point here based on the identical other ideals

I won't disagree with your thoughts, but believe what I described would fit our current usage of our motorhome at the lowest cost per mile for operation and should be less expensive in the initial purchase price. Both may be flawed opinions, but they are just that, opinions. Regardless, at 70 I don't see any changes from our current coach to anything else in our future.

Seems like a gas engine could not handle a large heavy motorhome.

MM.

If we expect to drive a heavy coach with carlike performance then you would be absolutely correct.

Based on my early years driving tandem and tri-axle dumptrucks with large gas engines, none of which had the benefit of today's technology or turbocharging I would disagree that a gas engine couldn't work. Those trucks moved loads up to 80,000 lbs quite well so with the advances in materials and engineering I believe it could work well, especially in lower mileage applications like RV's.

[Mr_Mark1]

hipower wrote:

gutfelt wrote:

hipower wrote:
This has been an interesting discussion and I can only offer my somewhat biased opinion based on many years of heavy vehicle operation as well as many years of RV ownership.

Our current coach is a 2003 Dutch Star with a Cummins ISC 350. It is no race car nor is it quick from a standing start. Does it do what I expect of it? Absolutely, and quite effectively. We have had numerous years where we traveled 10,000 plus miles and regardless of which coach we were driving they all did the job. Currently we are traveling about 2,500 miles per year and from a point of size and investment we could get by with less coach until we park for extended periods of time and the room is more important.

If I had the luxury of designing a coach chassis from scratch based on our use today it would have a 500+ c.i., turbocharged gas engine in a rear mounted configuration. Backed by a 8-10 speed automatic transmission with air ride suspension and air brakes. Obviously such an animal doesn't exist, and the closest thing to what I describe was the recent Workhorse rear engine chassis which had a short life and was overpriced, in my opinion with, very limited numbers of manufacturers offering them in their lineups.

Obviously this diatribe doesn't answer the OP's question, but my take on this whole thing is simple, if acceleration is a major factor in a buying decision maybe motorhomes aren't the best way for someone to travel.

BUT a 500++CID turbo diesel will still out perform your gas idea that's the point here based on the identical other ideals

I won't disagree with your thoughts, but believe what I described would fit our current usage of our motorhome at the lowest cost per mile for operation and should be less expensive in the initial purchase price. Both may be flawed opinions, but they are just that, opinions. Regardless, at 70 I don't see any changes from our current coach to anything else in our future.

Seems like a gas engine could not handle a large heavy motorhome.

MM.

[Cloud_Dancer]

IMO nobody is going to win or lose this discussion.
What makes me the winner is that I selected the most correct engine/transmisson/overall ratios/wheelbase/tire size/airbag size and spring rates/etc for the total weight I wanted to move, in the way I wanted to move it. I'm satisfied with everything I knowingly selected. The roof design was substandard (to say the least), but it doesn't enter into the thread subject.
What DOES enter into it, is the importance of the correct method the driver needs to use in order to get maximum acceleration performance in a DP like mine.

[hipower]

gutfelt wrote:

hipower wrote:
This has been an interesting discussion and I can only offer my somewhat biased opinion based on many years of heavy vehicle operation as well as many years of RV ownership.

Our current coach is a 2003 Dutch Star with a Cummins ISC 350. It is no race car nor is it quick from a standing start. Does it do what I expect of it? Absolutely, and quite effectively. We have had numerous years where we traveled 10,000 plus miles and regardless of which coach we were driving they all did the job. Currently we are traveling about 2,500 miles per year and from a point of size and investment we could get by with less coach until we park for extended periods of time and the room is more important.

If I had the luxury of designing a coach chassis from scratch based on our use today it would have a 500+ c.i., turbocharged gas engine in a rear mounted configuration. Backed by a 8-10 speed automatic transmission with air ride suspension and air brakes. Obviously such an animal doesn't exist, and the closest thing to what I describe was the recent Workhorse rear engine chassis which had a short life and was overpriced, in my opinion with, very limited numbers of manufacturers offering them in their lineups.

Obviously this diatribe doesn't answer the OP's question, but my take on this whole thing is simple, if acceleration is a major factor in a buying decision maybe motorhomes aren't the best way for someone to travel.

BUT a 500++CID turbo diesel will still out perform your gas idea that's the point here based on the identical other ideals

I won't disagree with your thoughts, but believe what I described would fit our current usage of our motorhome at the lowest cost per mile for operation and should be less expensive in the initial purchase price. Both may be flawed opinions, but they are just that, opinions. Regardless, at 70 I don't see any changes from our current coach to anything else in our future.

[gutfelt]

hipower wrote:
This has been an interesting discussion and I can only offer my somewhat biased opinion based on many years of heavy vehicle operation as well as many years of RV ownership.

Our current coach is a 2003 Dutch Star with a Cummins ISC 350. It is no race car nor is it quick from a standing start. Does it do what I expect of it? Absolutely, and quite effectively. We have had numerous years where we traveled 10,000 plus miles and regardless of which coach we were driving they all did the job. Currently we are traveling about 2,500 miles per year and from a point of size and investment we could get by with less coach until we park for extended periods of time and the room is more important.

If I had the luxury of designing a coach chassis from scratch based on our use today it would have a 500+ c.i., turbocharged gas engine in a rear mounted configuration. Backed by a 8-10 speed automatic transmission with air ride suspension and air brakes. Obviously such an animal doesn't exist, and the closest thing to what I describe was the recent Workhorse rear engine chassis which had a short life and was overpriced, in my opinion with, very limited numbers of manufacturers offering them in their lineups.

Obviously this diatribe doesn't answer the OP's question, but my take on this whole thing is simple, if acceleration is a major factor in a buying decision maybe motorhomes aren't the best way for someone to travel.

BUT a 500++CID turbo diesel will still out perform your gas idea that's the point here based on the identical other ideals

[hipower]

This has been an interesting discussion and I can only offer my somewhat biased opinion based on many years of heavy vehicle operation as well as many years of RV ownership.

Our current coach is a 2003 Dutch Star with a Cummins ISC 350. It is no race car nor is it quick from a standing start. Does it do what I expect of it? Absolutely, and quite effectively. We have had numerous years where we traveled 10,000 plus miles and regardless of which coach we were driving they all did the job. Currently we are traveling about 2,500 miles per year and from a point of size and investment we could get by with less coach until we park for extended periods of time and the room is more important.

If I had the luxury of designing a coach chassis from scratch based on our use today it would have a 500+ c.i., turbocharged gas engine in a rear mounted configuration. Backed by a 8-10 speed automatic transmission with air ride suspension and air brakes. Obviously such an animal doesn't exist, and the closest thing to what I describe was the recent Workhorse rear engine chassis which had a short life and was overpriced, in my opinion with, very limited numbers of manufacturers offering them in their lineups.

Obviously this diatribe doesn't answer the OP's question, but my take on this whole thing is simple, if acceleration is a major factor in a buying decision maybe motorhomes aren't the best way for someone to travel.