Wow, I think your friend is misleading you. A diesel needs to be rebuilt every 80-100K? Not a chance! These should go a half a million miles or more. In the years you're looking at, they don't have cats on them, not sure they even have an EGR(Exhaust gas recirculation) valve.
As far as fuel filters, the procedure varies from cummins to cat, but generally the same. About every 10k miles, you need to change it. On the cummins, it's right on top of the engine. Lift up the bed and there is direct access. Unscrew it, screw a new one on and prime it three times with the ignition switch. You're done. On the cat, they use a filter that looks like an oil filter. Fill it with diesel, screw it on and there is a hand prime right on top of the engine. Very simple.
Oil changes are identical to a gasser, just with more oil. DP's also hold more fuel. Mine holds 90 gallons, so going a longer distance you don't have to look for fuel as often. My old gasser held 50 gallons or so. The old '82 P30 we had, had a 30 gallon tank up front, and a 70 gallon out back. I remember my dad always having problems with vapor lock trying to get the fuel from the rear tank up to the engine.
The brakes are a huge difference from the hydraulic on the gasser to the DP's air brakes. The air brakes were designed for extra heavy loads. The hydraulic brakes are made for more of a light weight application. I no longer feel like i'm white-knuckling it when I drive my RV.
Tiffin builds a great motorhome from what I have heard. They are built in red bay, alabama and the owner of the company really stands behind his product.
The tiffin name has been around since the late 70's or early 80's. That should tell you something. How much is he asking for the unit? Do you have the link to it you can share?
