My 700R4 has 190,000+ miles on it and I think it is starting to go. It wants to rev to 1500 to 2000 when I put it in neutral at the red light. It also wants to stay around 2400-2500 rpm's when I am at 70mph (2.73 gears) on the interstate when it used to be around 2000 rpms. The question here is if I decide to get another tranny from someone else, will other years fit mine without problems? (mine is a 90 model) or should I worry about the tranny and just keep on going until it goes? Or should I rebuild it for a local quoted price of $800?

Any help deeply appreciated.
Thanks

 

the highway thing sounds like your torque converter is not locking up. make sure you're in OD and check to see if you're converter locks up after you shift inth 4th.

 

I'm definately in OD but I don't know if my torque convertor is locking up or not. How do you tell that? One suspect if that is the case, is my B&M shifter. It has a relay that might cause that problem. Never thought about that until now.

 

slowly accererate to about 40 mph or just when your car shifts into 4th. after the 3-4 shift, you should see the rpm's drop again by about 200 or so. this is the TC locking up.

or, and i believe this works though ive never tried it:

take a small piece of wire and connect the top right and top left terminals of your ALDL. this locks the converter in all gears except 1st. one the car shifts into 2nd you should see the rpms drop below normal.

 

If you decide to pick up another used trans, try to stick with an 88 or newer unit. They made some design changes on the later 700r4's that are supposed to make them more durable than the earlier ones.

 

OK, I will try the 40 mph thing tomorrow. Hey thanks for the info on the 88 or later thing. I was thinking about buying an 86 model that had just been rebuilt. It has a TCI lock up switch in it and a corvette servo in it for $400. I guess I will keep looking for trannies.