I am looking to purchase my first Rv. Requirements are 24-33ft, with a rear bedroom and bed over cab, and under $25k. What is everyone's thoughts on Ford E450/550 based with the 6.8l V10 vs GM C5500 based with the 8.1l V8? Long term reliability, power, cost of repairs?

Avoid the Ford e series with the 4 speed trans.

Of the 6 e450 chassis at work with that trans all are on there 3rd or 4th replacement in less than 200k miles. It's all stop and go city driving but doesn't give me good feelings about long term use in a personal vehicle.

The 6 speed seems to be holding up much better.

I have around 125 E series Ford buses in my fleet and just got rid of close to 20 C series GM buses.

The engines and transmissions have held up very well in all of them but the GM engines have a zero failure rate and about the same as the fords with the trans.

If you buy a ford make sure it is the v10 and not a v8. The 5.4 hates life in a big bus.

The GM buses I had all had solid front axles with king pins. PITA to change and didn't drive as well as the fords.

Probably 90% of the non maintenance repairs on these buses are wonky electrical and AC failures. Powertrain is pretty solid all the way around.

Convert the trans to quality synthetic fluid and add a cooler. I was in a Ford fleet with E chassis and when we did those two things we greatly reduced the amount of failures. Also Ford provides an add on filter for after a trans failure. Ford would prefer you replace the radiator due to the inability to completely remove all of the debris out of the old cooler due to the internal design of the cooler. I would drop the pan and service it as soon as you buy it.

Have a f250 with the v10. I think it’s a great engine. I was even able to do the spark plugs without much issue. And it’s towed my 5,000lb camper all over.

If one comes up with a GM 6.0 Liter, I wouldn't be afraid of it.  The 6.0 liter GM gas engine is solid and close to the power of the 8.1.

I haven’t had any problems with mine except for coil packs going bad I always keep two extras in the vehicle. They’re a quick swap except for the rear one on the passenger side

Had one go last fall, decided to just do all of them. Probably a good idea to carry spares.

I had one go bad so I just did that one. 4 months later had 3 go bad while towing my trailer. Now all replaced and the ones that were still good and the correct socket for the hold down bolt travel in the excursion with me.

I love Fords but 496 cubic inches.