I think there is something wrong with my tranny or rearend. (I'm clueless when it comes to this stuff) I'll be driving at around 30 or 40, and when I step on it, as it downshifts, there is a thump, kind of like a skip. Doesn't sound or feel good. Any ideas? My truck is a 97 f150. It's a 2wd regular cab. I haven't done any mods or anything to this part of the truck.

Thanks for any help.

josh

 

My shift accumulator spring went bad on my 4r70w (1st to second gear) and it acted exactly as you described, only at lower speeds. If that is the case I wouldn't let it go because the broken spring can scar the cast case and you'll need a complete rebuild instead of a spring replacement.

 

hey, thanks for the reply. I did some more investigating. It only happens when I am in overdrive at around 30mph and step on it hard. Any other thoughts?

Short Circuit, was this the case with you?