Does anyone know if I can replace the 3 speed auto transmission in my 1981 Audi 5000s with one from a 1989 or 1990 Audi 100? My understanding is that the 100 and 5000 series were very similar. I'd like to pickup a spare - the local u pull it is having a sale, but they dont have one from a 5000. I replaced the original with one from a later model (the cooler is in the rear instead of on the side) and it worked ok. Now this one is slipping and I cant make it stop. Any input would be greatly appreciated.

Thanks

The simple answer is, "yes" you can. BUT, the 087 3 speed automatics came with several different final drive ratios, valve bodies, governors, and torque converters. The various transmissions are designed to shift at different points based on the horsepower of the engine and the weight of the car. Your 5000 came with a 100 hp engine. The newer model Audis with the 3 speed automatic including the 100 and 200 were 135 to 165 hp. Using a valve body/torque converter combination from a newer transmission may give you a few surprises as far as the stall speed, shift points, and the shift firmness because they were designed for higher horsepower heavier cars.

If you look in the Bentley Manual for the later version cars, there is a technical data chart and a major component exchange chart that is helpful as far as deciding what components will work best in your specific application. Most of them will fit, but you may not like how they work! Audi engineers spent thousands of hours getting this kind of crap (minimally wrong) right in each specific application.

Chumley