I've already had to replace the capacitors in the PCM of my 93. I've also had to replace a bad capacitor in my VIC. I had a spare and a broken TCM so I thought I'd check to see if there were any (possibly bad) capacitors inside. There's only one. After I replaced it my shifting has improved noticeably. I had previously adjusted the kickdown cable shorter so it would shift better. Now I've adjusted the cable back and it shifts even better than before.
I did this on my 93 4.0 with the 42RE and one of the TCMs is a 94 so I think this will work for the 93-95 42RE TCMs. Not sure if the V8s have a TCm and I'm pretty sure the later models combine the TCM into the PCM. Anyway, here's how you do it:
Here's the TCM.
Use pliers to carefully bend the tabs up.
Here's the inside of the TCM. Just one big capacitor to replace. The one you want is a 470 microfarads at 35 volts, or at least all three of mine were.
One screw to get the board free of the case.
I'm not going to go into detail on the actual soldering because it's pretty well covered in other posts and on youtube. Also it takes two hands and I can't take a picture and solder at the same time. I will say that a solder sucker and solder wick help a lot. The white stripe needs to point the same way when you install the new one as the old one. I tested all three of the one's I have and all three old capacitors were bad.
Clip the tails down so they don't short out on the case.
The finished solder joints.
One new capacitor installed and ready to go. No nasty potting compound here!
On the TCM that actually went bad this relay was the culprit. Notice the burned pin. I couldn't find a replacement and junkyard TCMs are cheap enough.
Hope this helps someone. I also went around and reflowed most of the through mount solder pins just to be sure since Jeep seems to have issues with cracked solder joints.