1988 F250 Automatic Transmission problems

My F250 has had transmission problems since I bought it cheap from a friend last year. I knew it needed a new seal as it was loosing a quart of fluid every month or so. Also, when the truck was not warmed up the transmission had a hard time going from 1st to 2nd.

Recently, the same problem popped up with the change from 2nd to 3rd. Today, backing up a hill the transmission slipped, refused to engage, and the engine was rev’ing out of control. I invested $1200 in the truck. The body and engine are still in good shape. Any advice as to how much financial pain I’m in for?

The overdrive transmission is much more expensive than the 3 speed. And it is costly to change from the overdrive to the 3 speed. Call a local shop that specializes in transmissions and get a price. The price will vary greatly from area to area.

You seem ready for the Berryman B-12. It’s an alternative to rebuilding the transmission. The stuff isn’t made for transmissions but it is recommended by a couple of people here.

The only auto available in an 88 'F-250 was the C6. Sounds like the vacuum modulator has a broken diaphragm. You should see the vacuum hose going into a curled (candy cane shape) metal tube on the passenger side of the engine…near the dipstick. If it is all swollen and full of fluid it will cause very, very late shifts, loss of trans fluid and what seems to be an oil burning engine. Cheap to fix ($30 part)…so many problems from one little part, the mechanic that fixes it looks like a hero. Make sure you don’t lose the little steel rod that goes between the vacuum can and modulator valve…they are application specific and there are several different lengths. It is also possible that you’ve done some damage to the trans as well but perhaps not; they’re pretty tough