here's the thread where i wrote about it, didn't wanna type it out again.

clicky! http://www.fastlouis.com/forums/viewtopic.php?t=46121

 

Copy and paste is your friend. Your bill comes to... LOL

Just FYI, a 700R4 will go into lockup in 3rd gear as well as in fourth gear.

If your TCC solenoid is slow to kick in for whatever reason it can certainly seem like it shifts, 1-2, 2-3, 3-4, 4-5, 5-6.

Actually what it would be is 1-2, 2-3, 3 with lockup, 3-4, 4 with lockup.

Until I realized that the proper way to check your tranny fluid was with the car hot, running in park, shifting through every gear selection, then back to park, just before you check it, I was ALWAYS a quart and a half low. I also had just about the same problem. Enough that I took off the TCC disengage switch from the brake pedal for a few weeks so the TCC would never lockup. Pretty much a really fast way to kill a transmission. So check your fluid level, and make sure your doing it right.

I REALLY noticed it at about 50mph approaching a hill. I'd be in 4th+lockup, start to climb the hill, I'd hit the gas as I slowed down, the tranny would downshift to 3rd, about at the crest of the hill I'd ease up, and the TCC would lockup and seem to bog the living bejesus out of the motor, like almost down to idle with shuddering and everything.

It also helps to have a properly adjusted TV cable. The TV cable is EVERYTHING to a 700R4.

On your brake pedal is your TCC disengage switch, which unlocks the TCC every time you brake (so that your car doesn't stall when you come to a light). You can safely disconnect the electrical connector which will make it so the TC never ever locks up. You can isolate the problem the TCC lockup in that fashion. Don't drive forever like that, kills the gas mileage.

TCC solenoid is accessible when you remove the pan, as well as all the switches and wiring for it, but I don't think thats it.