I have an 89 f150 5.0 aod. when i am driving it shifts fine but when i go to slow down for someone infront of me then ease back in the throttle if shake the **** out of the truck.
please help

 

sounds like worn u-joints. check by trying to see if there is some give and play in the driveshaft.

 

i have check the joints they are good . thats what i thought it was. when i go to the floor with it it doesnt shake just at light throttle.

 

Does it feel like an engine miss?

 

Okay let me throw out a few more... Transmission mounts, torque converter mounts, shocks, out of balance tires....hell if I know

 

wow could be alot of stuff, if you got a check engine light on then go get codes pulled? afew months ago my truck would jerk after letting of the gas turned out to be the TPS. but i would go have all the mounts checked and everything. I know u didnt say nothing about it shaking when hitting the brake but ill throw this in anyways if it is shaking when u brake its the rotors......be sure to let us know when u find problem

 

I have no idea i have changed the tps, the iac, checked the mounts adjusted the kick down, readjusted the timing. Just blowes my mind. And i have no mil on. Im about to carb it with a c6 and be done with the efi

 

Have you tried knocking it out of gear at the point you want to slow down?

That might narrow down some possibilities.