My 90' F150 with a 302 and an AOD trans has a horrible stuttering problem in 3rd and fourth under light to moderate acceleration. The trans refuses to downshift to third when the gas is pressed and shutters and clunks hard up shifts fine though but still stutters. The issue does not occur if the truck has sat for a while but happens continuously once its been ran for a while. Any help would be appreciated as i drive it daily.

 

If its shuddering while accelerating, and not while shifting, I suspect you actually have a misfire problem, not a transmission problem.