hI, i HAVE A 1980  AOD  IN MY CAR,the trans WILL GO THRU 1-2-3- BEFORE 20 mph no matter how much throttle you give it,it does NOT slip in these gears. it goes into overdrive at 40 MPH and it slips when going in and will slip when trying to accelerate in overdrive,
the fluid is a little overfull,but does not smell burned, it also has a B&M shift kit in it also, the kick down rod is gone and a spring holds the kick down lever towards the engine. I bought this car recently and it had this problem when I purchased it. can  anyone tell me what the fix is for this problem?