DIESEL PUSHER vs FRONT ENGINE DIESEL - RV-Dreams Community Forum

foxriverguy · RV-Dreams Family Member

DIESEL PUSHER vs FRONT ENGINE DIESEL

RVDude · RV-Dreams Family Member

I'll kick this off with perhaps a perspective change. Since the rig will be camped a whole lot more than driven I would start with the floor plan and storage requirements which work best for you first and foremost and then almost, but not quite, skip right over DP vs FRED.

Now, as a DP owner - only because of my storage desires - I will say the full on air everything is simply a dream of a ride and a maximum of control. Personally, I started with my living/storage needs first and backed into chassis. Yes I did have some chassis requirments, but what rode on that chassis came first.

Penny and Paul · RV-Dreams Family Member

And of course there's the ever popular DPs have the genny in front, not under the bed...

Jim01 · RV-Dreams Family Member

I don't have any first-hand knowledge, but this year, down in Florida, we were parked next to an RVer who had traded up from a Ford (V-12) to the FRED chassis. He told me that he really liked the FRED chassis. it had more power and he said that the diesel engine was much quieter than the Ford engine.

If you're going to travel a lot, I'd sure consider the air ride suspension on a DP though. Also, make sure the FRED chassis has enough ccc for your needs.

Believe me, the weight that full-timers carry really adds up. More than you would think.

Jim

bjoyce · RV-Dreams Family Member

As a former gas motorhome owner and current diesel pusher owner I need to ask the question, "why does it have to be diesel"? Diesel is more expensive than unleaded but you get a bit better mileage from the same horsepower rating from diesel which makes up for it. But diesel chassis are more expensive so it will take years of mileage savings to make up for the small fuel savings. Recent side-by-side tests of an equivalent Winnebago diesel pusher and Workhorse gas chassis had the gas chassis outpulling on a grade.
I really like my 370 Cummins ISL on a Spartan chassis and prefer it to my old Workhorse W22 with a Vortec, but it cost me a lot more money.

ahoweth · RV-Dreams Family Member

I will drop a few ideas on you. First a FRED will have a long drive shaft probably with carrier bearings that will have to be maintained. Second the engine noise is quite a bit more on the FRED simply because the DP engine is further away. The FRED also has the ever present engine hump of a front engine RV. Air ride is really a big deal. These may not be big deals for some but they were for me!

JMO

bjoyce · RV-Dreams Family Member

I will now try to put my helpful hat on.
There are many chassis choices for diesel pushers, but only Freightliner makes FRED and it is fairly new. That means there are fewer choices of coach manufacturers with FRED, which might not matter if you have already found a particular motorhome with a FRED that you like. With a diesel pusher you can often get more choices of engine size and brand, number and placement of air bags, and if it has independent front suspension (IFS). These all matter. You can get the lowest optioned Freightliner DP chassis or big tag axle DP on a monocoque chassis with a huge engine. Basically you have a lot more choices and decisions with a diesel pusher but FRED comes in one basic flavor, a direct replacement for the Ford gas chassis.
Another very interesting choice is the various Super-C motorhomes which are also front-engine diesels but with semi-truck fronts.
Right now if you ever want to go into Mexico I would be looking at a one to three year old motorhome that uses a diesel engine that does not require ultra low sulfur diesel (ULSD) as the new engines do.

foxriverguy · RV-Dreams Family Member

Bill:

Will you elaborate on the going into Mexico with a MH that does not have the newer diesel engine?

Thanks,

George

RVDude · RV-Dreams Family Member

The USA and Canada adopted a new standard of diesel fuel called ULSD (Ultra Low Sulpher Diesel) so that the new (a.k.a. 2007 and newer) diesel engines can run with super clean emissions. These engines use a special particulate exhaust filter that must have this ULSD fuel or the exhaust filter will clog thus requiring very frequent and costly service. Think of it as the same type of situation when the catalytic converters were put on cars and what happened if you burned the old "leaded" gas. Same concept.

Well, Mexico has NOT gone with the ULSD fuel standard and as such, if you burn the old LSD diesel - the stuff in Mexico - in these newer engines, well, you're going to have some problems with that filter. The rest of the engine is fine. This is not to say ULSD is NOT available in Mexico, but, it apparently is very hard to find and as is common of fuel in Mexico of unknown quality.

With that said, technically, note I did not say legally, NOT ALL 2007+ diesel engines HAVE to run ULSD. If your engine does NOT have a particulate filter, then the old LSD (Low Sulpher Diesel) fuel which is what Mexico predominantly has and we used to have, is perfectly fine. For example, the Cummins ISM will not use a particulate filter until 2010 or later - but to legally meet the emissions requirement, note I said legally, it must burn ULSD. However, anyone with an ISM right now can technically burn either fuel with no engine concern at all.

Now you're probably particularly exhausted!

-- Edited by RVDude at 07:39, 2008-06-05