I have an '87 Camaro LT LG4 with the 700R4 auto tranny. I bought the car used exactly a month ago, and it has had this problem ever since I purchased it. I will hopefully have the time to have it looked at and repaired sometime this week depending on cost, but I would like your opinions first...

After I start the car, as I shift from P into R, D, whatever - the car will jump. It's not too bad when it's warm out, but it still does it enough for you to tell it is NOT supposed to do that. When it's cold or the car has sat overnight, it jumps very badly. The odometer only reads 56xxx, but I'm guessing the car has 156xxx miles on it realistically (if that helps). At first, people were saying it was most likely the mounts, but after I had it looked it the guy said the mounts were okay.

Any clues/tips as to what is realistically causing this? Other then this problem the tranny isn't giving me any other problems. Sounds and shifts just fine. Any help would be very appreciated.

 

Sounds like a transmission mount to me. Or possibly the U-joints.

The transmission mount is a really easy fix and the U-joints aren't that bad.

Get underneath the car and look at the tranny crossmember...in the center is the trans mount. Look at it and see if it is broken or loose. If so, replace it. That is probably the problem.

 

I, too, have the same problem. Mine's also an 87' LG4 w/700R4. I know it's not my tranny mount, I've already checked that. But, like he said, once it warms up, it doesn't do it. The car shifts hard and jumps when the car is cold. Once it warms up, everything is fine.

 

High idle speed maybe?

 

no, it's not that... my car idles at about 700RPMs. plus, that wouldn't make the car jump and shift hard from 1st-2nd though.

 

It could be normal, there's an accumulator in the auxiliary valvebody that early 700R4's don't have that softens the shift out of P.

 

Ok, that would make sense, but what about the shift from 1st-2nd? My buddy said it maybe that my tranny is just getting tired?

 

I stumbled upon this in another thread. According to TKO, they do have an aux. valve body.

Thanks for the input given so far, guys.