i just bought a 1998 mustang 3.8L auto trans and was wondering if anyone has any problems with them it down shifts hard and at 45 mph it seems to shift in and out of overdrive take it above 55 or so and it stops is this normal or is there a problem with it im a ford man but old school and this new age electronic stuff has me stumped any help would be great before i go back to the dealership and make an *** of my self

 

On hills it will downshift. On level ground with a steady right foot it should not. Don't pump on the accelerator like a woman driver.
Cruise control makes it worse on hills. Turn it off. Also you could use the O/D cancel switch below 55 to elimate the issue.

 

it does it while at a steady 45 you can feel it shift in and out repeatly and when slowing down like at a light it down shifts very hard enough to jerk your head almost like a trans brake

 

this used to happen to me. turned out the seal between the driveshaft and transmission chamber was broken. could be the case but i dunno.