1989 Ford Aerostar?

transmission needs replaced, and your overdrive is shot...but your car is 17 years old too.

Does the trans work okay in the D position does it shift through all the gears okay? Does it go into overdrive at the right speed? if so it is the linkage that is out of adjustment. The overdrive isn't effected until the car is actually ready to go into overdrive so its not a overdrive problem just make sure it does shift okay.

It sounds like your shift linkage is worn or misadjusted.If it works normally except for the fact that you have to move the shifter a little further than normal I would bet you can overcome that with a little bit of cable adjustment or maybe the cable is not firmly seated at either the transmission on where it attaches to the steering column.That's where I would look first.I trust however that you have checked your trans. fluid level....Right?

The shifting lever is not in sync with the gear indicator, that's my best guess. I have the same problem with my Grand Marquis if I read the question right. You basically have to take your best feel of where the gear is by how the shifting lever sits compared to what the gear indicator shows.

sounds like you have an aod trans (automatic overdrive). You might be lucky and just have a stuck valve. Purchase some "TransValve Fix" at local auto store and follow directions to the letter, good luck.

You should change the fluid and filter on that tranny. You just might save it. If you don't you Will just need to buy a new one because it Will die on you. So try changing the fluid and filter and see if does better. If no difference its too late.

Your overdrive band is slipping. In drive, the O/D band is not used sou you may be able to go quite awhile if you do not use O/D.

Did you check transmission fluid?

Your shift linkage may simply be off.

The JazzStud is right.

youneedanewtrans