Gas or diesel?

new2motor · 08-17-2008, 05:22 PM

I am looking at the Winnie 26P (gas) or the View and Navion (V6 diesels)as my first motorhome. Towed trailers for years with various gas trucks, and always had power issues after 60-80,000 miles on mountains (even Poconos on I-81 or I-476). Any experience why the 26P would be better or worse than the smaller diesels? Any other advantages or one or the other?

new2motor · 08-17-2008, 05:22 PM

I am looking at the Winnie 26P (gas) or the View and Navion (V6 diesels)as my first motorhome. Towed trailers for years with various gas trucks, and always had power issues after 60-80,000 miles on mountains (even Poconos on I-81 or I-476). Any experience why the 26P would be better or worse than the smaller diesels? Any other advantages or one or the other?

porscheracer · 08-17-2008, 05:32 PM

I like the 16 MPG (realistic, and measured - by us) in our V-6 View, and it will outrun our Vectra (350 CAT) handily. If you're towing much trailer, though, its 154HP might be anemic.

But, then, I'm a diesel fan - my biggest reason for never considering any of Winnebago's traditional C's.

new2motor · 08-17-2008, 05:45 PM

Thanks for the reply! What would you call "much trailer"? Would you include a small car in that cataogry (e.g. Honda CRV)?

John_Canfield · 08-17-2008, 06:13 PM

Hi and welcome to the forum!

Always compare torque - that's what gets your load up the hill.

MrTransistor · 08-19-2008, 08:03 AM

Hello new2motor,

Okay, lets put this to rest. "Horse Power" is what moves you and gets you up the hills. Burning fuel is measured in ˜Pounds' per ˜HP' per ˜Hour'. Not Pounds / Torque / Hour.

As an example; with a ten foot breaker bar, it's fairly easy for me to exert a Torque of 1000 Foot / Pounds, but I couldn't push the RV on level ground much less up a hill because I am only able to produce about ¼ HP at a dead run. (well, not any more)

A jet turbine engine has relatively little Torque but you can't argue about its power because that Torque is produced at a very high RPM, i.e. HP.

If two engines have the same Horse Power but one is produced at 1500 RPM and the other is at 3000 RPM, then the one at higher RPM will be geared down by twice as much to produce a road speed that is the same as the one at 1500. And the gearing will give it the same amount of push to move the vehicle.

The Torque figure for an engine is only used to calculate the Horse Power. That is why the RPM of the maximum Torque is not the same as the RPM of maximum Horse Power.

Horse Power = Torque * ˜RPM' / 5252

The maximum Torque for the CAT C7 RV engine is 860 ft/Lb and occurs at 1450 RPM. But, at that RPM, the HP is only 235. It only produces 730 ft/Lb of Torque at 2400 RPM but low and behold the HP goes up to 350 because of the increase in RPM.

Torque is just a measurement of Force, kind of like PSI. Horse Power is a value of Work and it takes lots of work to move an RV up a hill. Torque by it's self is pretty meaningless unless you know at what RPM it occurs. 1,000,000 ft/Lb at 0 RPM by definition won't move anything! But 200 ft/Lb at 15,000 RPM gets a Formula One race car going at a pretty good clip.

As to what to buy, a Gas engine that produces 350 HP at 4200 RPM or a Diesel that produces 350 HP at 2400 RPM, the choice should not be made on the Torque rating of the respective engines. Rather consider the cost per mile to drive with the number of miles per year and total miles you expect to drive over the life of the vehicle.

For Truckers, the choice is simple, Diesel. A million miles between overhauls, 35% better mileage, and less frequent fuel stops more than offset the initial cost.

In an RV, the question is less clear. The larger the coach, the less MPG you'll get. That alone may make the decision for you. A gas engine costs less to purchase, that's a plus, but you're looking at increased fuel costs, more frequent fuel stops, and if you drive enough, a likely engine overhaul at some point down the road.

And sometimes, it's just comforting to know that big 2000 Lb. CAT or Cummins is back there pushing you!

PushingaBigLoad · 08-19-2008, 08:45 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by MrTransistor:
Hello new2motor,

Okay, lets put this to rest. "Horse Power" is what moves you and gets you up the hills. </div></BLOCKQUOTE>

Actually, Torque [b]gets[/b you rolling and HP keeps you rolling, to a certain point. In our coaches, if not for torque, we would not be moving anywhere, except down a very flat highway.

John_Canfield · 08-19-2008, 08:57 AM

Horsepower is simply a derived number. Here is a useful article for those that care.

Rocket Heart · 08-19-2008, 12:05 PM

No two ways about it - a diesel will out pull a gasser every time!! Can we hear an Amen.....Point A: What is best is what you can afford and can do the job you need it to do. Point B: If that's towing cars or trailers up and down mountains then the diesel is the way to go - providing you go back to point A and factor cost into it.

I own a gasser - a very nice gasser -it will not out pull the diesel - it may out run one though and I saved a heck of a lot of money on my choice. The diesel guys don't recognize gassers but others do and they are all impressed with my gasser and so am I.

-Gramps- · 08-19-2008, 05:16 PM

My 26,000 lb gas powered coach has the same carrying capacity as a 28,00 lb diesel chassis. Then again it is not your typical gasser. Winne makes a couple of coaches on the same UFO as mine. However you won't fine any used ones..not yet anyway.

porscheracer · 08-19-2008, 05:19 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by new2motor:
What would you call "much trailer"? Would you include a small car in that cataogry (e.g. Honda CRV)? </div></BLOCKQUOTE>

I'd consider the CRV as probably the "best" toad for a View. But it is at the upper limit of the early models' tow rating. The '09's are rated at 5000# (as are all the V-6's, technically - but we won't go there). I'd consider 3500# (or less) as the maximum I'd consider towing very far - especially if there are any mountains in your path.

One nice thing about the View: it is small enough that unless you're planning on some off-roading, there's almost no reason to drag a toad along. It will go almost anywhere you could get a dually pickup truck. I've parked in more than one "conventional shopping center" parking lot with no problems.

On the gas vs diesel argument:
The View is supposedly offered (optionally) with a gas engine, but I know nothing about it.
Gas engines are several thousand $$ cheaper, even in the units that offer an option. Maintenance is marginally less, for the first 100K miles or so, on a gas engine. Fuel (as of now, but not historically) is cheaper per gallon - but mileage is ~30% better with a diesel.

If you're going to be semi-fulltiming, the View MAY be a tad small. We bought ours as a 2nd motorhome - for long-distance traveling, at <1/2 the fuel costs of the Vectra. Assuming diesel stays at $4 or above for the next 5 years, it will pay for itself - literally; and we won't have put an additional 250K miles on the Vectra.

If you're going to be parked at campsites the majority of the time, with only occasional or short trips, (say, 15K miles or less a year) I'd go with gas. Otherwise, diesel. And if you go diesel, make SURE you get a diesel generator. An LP genset is almost an "emergency use only" item.

MrTransistor · 08-19-2008, 07:36 PM

Hi All,

Well, I guess this is one for Mythbusters.

We had an Adventurer with the Ford V10 and it pulled hills like a champ. It's HP to weight ratio was much better than the Horizon we are in now and, as a result, pulled 9 mile hill here in Albuquerque at least 10 MPH faster. I have nothing against gas power. I can't imagine a diesel Triumph Bonneville!

I am in complete agreement with Norm; if you get a diesel, make sure you get a diesel generator. The LP versions tend to drain the LP tank very fast. Owing to the heat content of propane vs. diesel.

porscheracer · 08-21-2008, 12:17 PM

Mark - Yes, I'm sure the Advanturer / Ford V-10 had a better power to weight ratio. The gas Aventurer was probably 7000# lighter, with similar peak horsepower to the Horizon. And due to the weeight and profile differences, it probably got similar fuel economy.

I'd hate to imagine the fuel mileage on a 30,000# gas-powered Vectra with 33 sq./ft. of frontal area and a Cd of about .70.

Since we're rattling on about diesel ecomomy - I have determined that the 18-20 MPG figures for the View were accurate for the 5-cylinder units. The V-6 gets 14-16 (which concurs with my experience). This is from Lichtsinn - since Winnebago would neither confirm nor deny it.