Bought a 93 Z28 for a song with a bad tranny. The trans worked fine in R, 1st, 2nd, and D/OD would only shift 1st and 2nd. when i got to 3rd motor just reved until i slowed down enough to let 2nd kick back in again. Decided to pull the tranny and tear into it after noticing that it looked as if it may have been out before. i.e. new TB cable improperly adjusted, inspection cover missing.

I kinda expected that the clutches would be toast, or maybe a piston would be missing a seal, or something obvious but no such luck. Only real finds were that the 1-2 accumulator spring was broken, a torrington bearings cover was broken, and the rear lube seal had a broken edge.

I fully intend to replace all the clutches anyhow, knowing the steels look so good maybe ill leave them. Going to move on to the VB this week, and hope to see something there.

This is in fact the first trans that i have taken apart, but from what i can tell all the bushings seem perfect, all the clutches seem to be in good shape, steels are clean, all the hard parts are perfect. I am kinda wondering if someone has pulled this trans before and did not adjust the TV cable properly (as i mentioned before there was no tention whatsoever)

what you guys think, am i going about this the right way? Is it possible that i am missing something due to my inexperience? Any help/comment would be appriciated.

 

nice job, did you use the manual to tear it apart, im toying with the idea of doing one myself??

Idk, but did you mess with the cable before you pulled it?? Is the 2-3 servo thing ok??

 

i actually used the DVD to tear it down. It worked flawlessly. As far as the special tools that are needed, i can see why you would need them, but i made some stuff i had work for me in place of those.

i am not seeing anything wrong with the 2-3 servo. but i am going to start pulling the valve body apart tonight, maybe there will be something there.

this is not my DD so there is no issue with feeling rushed, if it were however i might not have decided to do this myself, if that gives you any help on whether or not to do it yourself.

 

i have the exact same problem, just happened a couple days ago, i havent had a chance to pull it apart yet but im thinking its my 2-3 servo. this would also be my first tranny project, what dvd/manual did you use and how did you pull the tranny out? did you pull the engine or lift the car and go from underneath?

 

I pulled the trans from underneath, you really only need to get the car up high enough to work underneath it. after you have the trans on the ground you can jack up one side and pull it out from under the car by lifting the tail shaft slightly to clear the frame rail with the top of the bellhousing.

here is a list of the special stuff i bought just to remove the trans, keep in mind i already had the wrenches, rachets, and sockets:

700r4/4L60 rebuild DVD (you may want to check to see if you need the "E")
http://cgi.ebay.com/ebaymotors/GM-70...sQ5fLiterature

450 Lb. Capacity Transmission Jack
http://www.harborfreight.com/450-lb-...ack-39178.html
Several people said that i would not need this, and after pulling the trans wet, i disagree. it helped while pulling the cooler lines and getting the unit back off the guide pins. I did the whole pull by myself.

4 Piece 3/8" Quick-Release Extension Bar Set
http://www.harborfreight.com/4-piece...set-99882.html
these offered enough length to get to the top 2 bolts and made the other ones easy as well, just put the universal below in the end of them and cranked on them.

3/8'' and 1/2'' Universal Joint Impact Set
http://www.harborfreight.com/3-8-eig...set-36846.html
this was by far the best universal i have used, it kept the socket in place while i guided it to the top bolts and it moves smoothly when at an angle, i highly recommend these.

I have not really located what i would think is clear evidence of the problem, but the 1-2 accumulator spring was broken, maybe you should consider dropping the pan and pulling that first. might save you some trouble.

Let me know if this helps

 

I have seen the pistons at the base of the drum crack, I like to install all the drums on a pump and air check assembly with compressed air.

On the VB look at valve train, I do a ton of these and realy seldom see VB issues.

Good luck----- can provide specs on things if you need during rebuild

 

Cool, good info. Thanks for the support.

Already went through the VB and found a couple of valves that did not move as freely as I thought that they should. (based on how i thought it should work)

Plan on air checking this weekend. keeping my fingers crossed.

BTW, thanks again to all for the support

 

So, I finally got it back together and in the car. I am having a problem though. My pressure is at 35psi and holding, regaurdless of the gear or TV cable position. The forward gears turn the tires, reverse does not seem very strong at all, and the tires rotate in N.

Any ideas?

I have read a few forums that mentioned that if TV lineup is incorrect it could cause this issue.

 

It turned out to be the TV boost valve not fully seated. Pressure came right up and car seems to drive OK. Working on adjusting the TV cable to get it dialed in now.

 

35 psi is far to low, this indicates a issue on the main line pressure circut, you have a big leak internally. I would suspect lip seals are not seated correctly. Reverse requires much more pressure, but at only 35psi I am not sure the reverse booster would see enough pressure to apply. Look for a big leak in the main line pressure circut DO NOT TRY TO DRIVE. at 35psi you will smoke the clutches.

This will not be a TV cable issue.... this is an internal leak of main line pressure.

Good Luck, Mike
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