i have an 88 5.0 with an AOD trans.. not too long ago i was driving down the road with it in overdrive at about 55. the car started to free rev.. it drives fine with it just in drive but as soon as the it tries to go into oveerdrive it revs... is there something i can do to fix it or have done or do i have to completely replace it? i bought the car after the trans had been rebuilt and it problem only has 12,000 additional miles on it since the rebuild. Thanks for all ur help!!

 

Whenever I feel slipping in any gear on
my 89 I check the trans fluid and find it
needs a little more oil. I made the error
of adding dextron oil once and found that
it causes slippage in ford trans. Needs mercron.

 

Sounds like yourlow on trans fluid or it needs a rebuild