Are large gas motor Rv's underpower?

[invmartyc]

At the risk of getting someone angry for me asking the same question they don't want to see again, that no doubt some people feel has been discussed enough.

Are gas Class A's underpowered to tow a toad in any area with mountains or large hills.

I have read people with gassers say that they are powerful enough for them to tow a toad anywhere. And I have read that no gas motor Class A has the power and that you need a diesel motor.

What is the truth, not opinion on this?

[Valkyriebush]

All you gassers passing DP is only because they didn't know they were in a race with you! 🙂
Banks made a big difference on my previous gasser 460. If your not happy with stock.

[Sully2]

Bird Freak wrote:
I had a 37 ft triple slide with a 8.1 gas engine and passed many dp's climbing hills pulling my toad. Never had a under powered problem.

I had back to back lottery winners too. Who do you think is going to be believed first?

[xctraveler]

Drove GM 8.1 liter engine over 150,000 miles in two coaches, always made the top of the hill. Could not keep up with my old Corvette from the line, or even with my RAV4, but it got out into traffic just fine with a little planning and patience.

Got me a diesel for my 3rd coach, Cummins ISC 380 HP. It is no faster off the line than the gassers - lots more weight. And so far it has made every grade I've tried. My son, who lives up in a holler on a mountain dirt road says he can tell the difference because he can't hear the engine roaring from 1/2 mile off like he could with the gas engines. My biggest expectation is longer life, my last coach had 110,000 miles on it and needed the interior rebuilt from use. Wouldn't put the $$ into the coach because I had used half or more of the expected life of the driveline. New gasser would have been fine but I wanted a diesel and DW found an acceptable floorplan in the diesel. I got the engine and drive line I WANTED and she got the living quarters she wanted.

[carringb]

william mcbride wrote:
The only experience I had on the subject was in a 37 ft Nemar with a 460 ford... It stayed in passing gear as much as not on level ground... I was test driving and I took it back after 5 miles and parked it...

That has about as much relevance as people's experience with the GM 6.2L diesel.

Motors have come a LONG ways since the mid-90's. The V10 makes 125 more HP than the most powerful 460 ever did (in stock truck form), and its available over more RPM. Plus, the current F53 chassis has about 5500 pounds more max GVWR, without needing a tag-axle.

[the_silverback]

I designed engines for 35 years. It is about horsepower and weight of the Motorhome. NOT TORQUE!! Except the more torque means more horsepower. So if a gas MH has a good horsepower to weight ratio it will do just fine.

[Doc15]

About all a guy can do is gather all the information he can and make a decision. Either way it is an exciting time you are going thru... even for a senior like myself who doesn't get as excited as much anymore like I wish..Have fun buying and even more using.. Best of luck to ya.

[invmartyc]

Well, I want to thank everyone for the information and I also appreciate the open minded kindness everyone extended. Being new to the RV scene I have been researching things for some time. It is nice to get the opinion of the people who actually are RVers! I have learned that, in most cases, the last person to ask for information like this is a salesman! The last few sales people I have talked to knew even less than me!

[rgatijnet1]

Since both the GM/Allison transmission, and the Ford V-10 transmissions, in newer years having a grade brake feature, the exhaust brake on the diesel is certainly not worth the extra cost above a gas powered coach.

[Doc15]

The only experience I had on the subject was in a 37 ft Nemar with a 460 ford... It stayed in passing gear as much as not on level ground... I was test driving and I took it back after 5 miles and parked it... Drove a similar rig with a 454 and it performed better... Still didn't buy it... I did as an old friend preached who had owned a half dozen coaches and waited until I found the right DP rig... It just happened to be a Foretravel with a 300 Cat.. One thing buying a gas is they are often not coupled with a Allison transmission and that is what you would miss even more than the diesel... These are not opinions but facts I discovered so I won't be dragged into an argument over the matter.

[Bumpyroad]

invmartyc wrote:
At the risk of getting someone angry for me asking the same question they don't want to see again, that no doubt some people feel has been discussed enough.

Are gas Class A's underpowered to tow a toad in any area with mountains or large hills.

I have read people with gassers say that they are powerful enough for them to tow a toad anywhere. And I have read that no gas motor Class A has the power and that you need a diesel motor.

What is the truth, not opinion on this?

hogwash
egos sell a lot more DPs than need does.
bumpy

[Ivylog]

" a gas engine should be good for 200-250k miles and odds are the rig will be old and falling apart long before the engine gets worn out. "
True and a mid-high level DP will be at mid life and the house will not be falling apart. In many ways it gets down to how long you'll keep the rig. I'm at 10 years and see no reason why I'll not have it in another 10 years. My cost to own for 20 years will be less than someone who buys and then trades two times on lessor MHs.

[valhalla360]

Tom N wrote:
Diesels are preferred at altitudes >10,000'. Because of the turbocharger/blower.

-Tom, W3TLN

This along with an exhaust brake is the significant difference. If you will spend a lot of miles in the mountains, it can be justification.

Torque only determines if you get up the hill and that is torque at the wheels. A lower gear will provide more torque, so as long as the engine isn't grossly underpowered, torque is a non-issue.

How fast you can go up the hill is mostly about HP. The only catch is people get nervouse running a gas engine at high RPM in a torque producing lower gear. Assuming the engine is in good running order, it won't hurt the engine.

Unless you are a carney putting 50-100k miles/yr, long term durability of a diesel is a red herring (even then it's probably overstated with newer diesels being much more complicated). With proper care, a gas engine should be good for 200-250k miles and odds are the rig will be old and falling apart long before the engine gets worn out.

[Tom_N]

Diesels are preferred at altitudes >10,000'. Because of the turbocharger/blower.

-Tom, W3TLN

[Ivylog]

It seems I get passed by gasser's more often than other DPs. At some point I'll pass them as they will be in the shop with serious engine problems. The more HP you get/cu in the shorter the life of the engine (both gas and diesel). With proper maintenance and some luck a gas MH is probably good for 200K trouble free miles while a diesel is probably 400+K miles. Both more than enough for most although those that pass me will not get 200K trouble free miles. Yes, I have a fairly heavy right foot and to pass me you will be working your gas engine at 90% while I'm at 50%.

[Community Alumni]

"I have had both diesel and gas and have never NOT made it up any hill I've tried."

X3