I recently bought a 2003 4.0 with 166k on it. The problem I am having is when accelerating from a dead start the entire truck will jolt, almost like I got a love tap on the bumper. It does it again when decelerating from cruising speed from 3-2 and right before I come to a dead stop at 2-1. It will do it every time. One other thing I noticed is sometimes when switching from reverse to 1st the TC stays locked when I shift while it is still barely rolling, instantly changing moving directions. Any ideas what is going on and what could be the fix? I've been looking for a junk trans to rebuild in my garage, but I'm on a limited budget that won't allow for the prices people are asking for those.

 

2003 4.0l Ranger will have the 5R55E transmission.

Good read here on problems with that transmission: Common Problems for The Ford 5R55E Transmission: Do You Know What They Are?

Test solenoids
And for sure add a 2nd trans cooler.

Google: 5R55E

There are some videos on fixing problems along with other information


Symptoms on automatics vary too much to say "yes, that's the problem", you are there so only you know all the symptoms, so read a few articles that others have posted and may be it will ring a few bells on your problem.

 

The jolt symptom can also be caused by the slip joint in the driveshaft. The lube get worn out and doesn't slip like it is supposed to, then does it suddenly. It is not a difficult fix but make sure you get a good lube fore it. I think Ford sells a packet of lube just for this application.
I have a manual transmission and it was starting to give the jolt symptom. I took the slip joint apart, cleaned it well and applied a good lube. I has been very smooth since then.

 

Was it doing it during the downshift as well?

 

It was so long ago that I don't remember all the details of the jolts. However, since I have a manual transmission it would not be as noticeable on downshift compared to taking out from a stop. I think an automatic would be more pronounced on downshifts compared to a manual but that is only an opinion.