Ok a friend of mine picked up a nice 91 Z28. Car ran great for about 3 days then bam it stopped shifting into 3rd or 4th. Well not really stop shifting but it goes into neutral instead of shifting to 3rd. I checked all the standard things. Tranny fluid, vacuum lines, electronics hook ups. Everything seems to be attached ok. My only idea was the overdrive cluthc being shot... But I'm not familiar with automatics so what else could it be.

 

does it go into reverse? probably not, its most likely the sun gear. it should be less than a grand to have rebuilt, have them put in carbon fiber discs and a corvette servo, it'll shift nicer than with a shift kit, and break tire into second if you have enough hp. The same thing happened to my last camaro. Good luck

 

Acctually it does go into reverse. The only gears it won't go into is 3rd and 4th. It pulls really hard in first and second and will break traction during that shift. Full throttle acceleration will go all the way up to redline in second then it is like it got shifted into neutral. Second pulling hard to redline then shift to RRRRRRAAAAAAAA redline and slowing down

 

The thing that I would try is to adjust the TV Cable if its not in sync it will have problem shifting between 3-4. Dont use the manual(self adjusting) it's very difficult language to understand.
Here is a very easy way of doing it:

700R4 TV Cable Adjustment
Press the 'D' shaped lock button on the adjuster and loosen the cable setting (The black housing that the metal cable is in will move forward). Now, have someone floor the gas pedal while you check to see if the throttle plate is open all the way. Usually they are off a little and will wiggle. Do whatever you have to do to get it open solid. Now, with the pedal still floored, press the 'D' button and pull the cable causing (the black tube) back as hard as you can (putting maximum tension on the metal cable) and release the button. You now have the engine, tranny and gas pedal all in sync at WOT. Mark the cable casing so if for some reason it gets moved you can know where to put it again. The problem with the 'self adjust method' is that it bends things and puts them permanently out of whack. It is also the full TV setting,
which is theoretically what the GM method does' then it may be that the 1-2 accumulator spring is broken (not uncommon).

David

 

thats funny, same thing happened to me the first day i got my 91Z i drove 150 miles to get the car and 5 min away from my house 3rd gear neutrals out. man i was so pissed!

 

Before you do anything that will be expensive check the governor at the back of the tranny, if its that it will only run you about $60. Mine did something similar but it wouldnt come out of first.

 

If it is going into third but free revving it is not an adjustment or governor problem.

 

I HAD A 91 FORMULA WITH A 350 TPI HAD THE EXACT SAME THING HAPPEN. TRY MANUALLY SHIFTING INTO THIRD, WHEN I DID THAT IT WENT IN BUT HAD NO POWER. WHAT YOU THINK IS SHIFTING INTO NEUTRAL COULD ACTUALLY BE THIRD. I HAD MINE REBUILT FOR THIRTEEN HUNDRED AND THEY DID A GOOD JOB. THEY SAID IT WAS A BEARING IN THE PLANITAIRY(SP) CARRIER.
I WOULD DEFFINATLY GET THE CORVETTE SERVO, HD 3-4 CLUTCH PACK, AND A STALL(IF YOUR FUTURE WILL WARRANT IT) IF YOU DECIDE TO REBUILD IT.

 

ok thanks for all the replys looks like I'm just gonna have to tell them to get it rebuilt... I'm gonna check out a few things today on the car and will get back to you. thanks

 

Hey You know a couple of weeks ago i had the EXACT same problem with my 89 R.S. Would run into reverse and could shift from 1st to 2nd but when it got to third it was like neutral. I couldn't figure it out so i gots a truck till i fix/sell the camaro. I'm thikning about selling it to a buddy of mine that wants to make it a drag car. If you find out the problem please let me know. contact at:
Another3rdGenRacer@hotmail.com
Thanks alot,
Ryan Major

 

The 3-4 clutch packs in all 700R4's have been a weak point. When I rebuild these units for Street/Strip, I always use the Borg Warner Hi-Energy .080 3-4 cluctches (8), along with the Trans-Go Performance Shift kit, Corvette servo, and the large boost valves (.500 & .296), Trans-Go hi-rev spring kit, etc. I have had no problems with the 3-4 clutch pack in over 6 years. If you have any questions concerning this, let me know?

 

I agree with ProBuilt. In this case, its NOT a shifting problem, but the 3-4 Clutchpack is TOAST, which unfortunatly is a weakspot of this tranny. There has been many advancements made to prolong the life of these clutches, the key is to find somebody who takes advantage of the technology out there instead of just "slapping some new clutches in there".