What year MH models are too old to consider buying?

I have a buddy with a 1987 motorhome that has a carburetor. That is to old. By 1990, most have fuel injection.

By the way I bought my 1997 Bounder when it was new, so that is NOT old - I keep telling myself it is just paid off, and not old . . .

I have a 30E floorplan. I did not want to go larger than about 30' because the engines of the time where not powerful enough to take a 20,000 RV up a hill and tow a car at a reasonable speed. Now they are, because they have changed to a larger capacity 5 and 6 speed transmission. My E4OD transmission is pretty much maxed out as far as being able to live with the load it is expected to carry for 100,000 miles. Normally the transmissions are expected to last well over 150,000 miles in a pickup, but their typical load is moving a 8,000 pound pickup in city traffic, with some hills, and sometimes spending time towing in the 15,000 - 18,000 GCVW range. Motorhomes do spend most of their time moving around 15,000 (my empty weight) to 21,000 GCVW (my weight while towing my Ford Edge. So I am not expecting as long of a transmission life. I do have a digital transmission gauge, so I can slow down when it gets over 215F, and will install a second cooler if it had ever run over 220 on the mountains or 200 on flat areas.

Problems that you might run into are leaking roofs, stains on the roof (from leaks) or perhaps some leaking plumbing. If they did not winterize the RV properly, then several hidden pipes might have cracked at some point. Check for water leaks near the water heater. The pump should turn on, pressurize the system, then stay off for about 5 minutes minimum before cycling back on.

Good luck with your search.

Fred.

Anything older than about 1991 will have a carburetor instead of fuel injection. Carburetor's work fine, they do drink a little more fuel than injected models. Expect about 6mpg on carbureted, maybe 8mpg on injected.

The suspension is the same on newer as it was on the older coaches. Chevy P30 chassis are weak while the fords are a little stronger.

Older coaches seem to be built better, but you also get no slides which is a desirable option. I love my slide, and now that i've had one I would not be without one. Just a few things to kick around.

It all depends on what type motorhome you are considering. Older gas-powered motorhomes had carburators rather than fuel injection, the 4L80 transmission in early Chevrolet chassis was worthless--later coaches used Allison transmissions. Chassis were made heavier-duty etc.
High-line diesel pushers like ours and similar units will probably go forever if cared for.
Carburators and 3-speed transmissions kept mileage low--4- and 5-speed transmissions with lock-up and fuel injection improved mileage in the early 90's. My dad's '89 Pace Arrow got 6.5 MPG on the same roads our '91 Pace Arrow got 8 MPG. Don't look for much improvement in the mileage of newer gas motorhomes. With DPs, bigger engines and emission controls have adversely impacted mileage in newer DPs. Weight with slides of course had a big impact. Late versions of our coach probably get around 2 MPG less than our coach, but they are heavier and have more HP.
Until you get more specific on what you are looking at, it is hard to give generalities.
Good luck!