Announcement

Collapse
No announcement yet.

T56 Transmission Issue

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • T56 Transmission Issue

    Transmission Experts: Please Read The transmission in question is a 2000 T56 that is normally mated to a mildly built LS1. A couple years ago I had my transmission rebuilt by a guy in a barn that I got a couple good referrals to go see. The only thing that was wrong at the time was that it would occasionally pop out of 3rd gear under engine braking. He did a standard rebuild on it and upgraded the 3-4 shift fork to steel with bronze guides. The other guides throughout were also upgraded. When I first got it back, I had an issue where the gear stick would try to jump out of 1st gear as I let the clutch out. So I tore the transmission back out and had him go back through it. He determined he had something shimmed wrong. So I get it back for the second time and everything seems great. Then I tried to downshift from 6th to 3rd on the freeway (I know, aggressive) and it was locking me out. I couldn't force or grind it in. I had to shift into 5th, then it would let me get into 3rd. On top of that, it was also leaking fluid. Just a drop here and there, but annoying to me. So this winter, I decided to cut my losses and take it to a professional shop to have it completely gone through and rebuilt again. This shop is very well known, so I figured they were the best guys to do the work. After a few weeks, they had it broken down and said they really didn't find anything glaringly wrong. They did see a few parts that needed to be replaced, but nothing catastrophic. So I had them replace what they recommended and put it all back together. I installed it a week later and went to test drive it a couple weeks after that. I backed it out of the shop no problem, but when I went to shift into 1st, it was like I was locked out. I couldn't get into 1st or 2nd. I was able to shift into 3rd, then second which was a little rough, then I could get into 1st with a bit of force. Drove it up and down the street, same issue. And it doesn't get any better. Tried double clutching, no difference. Bled the clutch again, no difference. Car seems ok without the engine running, but not with it on. The shop said I need to tear it back out and bring it back to them to be gone through. I can do this (getting really good at pulling the trans. I can go from a fully assembled car to having the trans out in less than 1 hour!), just not my favorite thing to do. They said they don't know what the problem is and don't have any ideas of other things I should try or test before pulling it out. They also didn't see any value in them test driving the car before I pull the transmission out. At least they're willing to help. I'm just a little apprehensive to pull it apart again without having any idea of what might be wrong since it seems fine without the engine running. Any thoughts or suggestions are appreciated before I pull this thing. A picture of the build sheet from my most recent rebuild is below. Thanks in advance!
    2000 Trans Am l 1967 Firebird

    sigpic

  • #2
    Stock clutch? Only time I ever had problems with mine going it to first or second was when I changed my clutch and the master was moving enough fluid and not fully releasing the clutch. Tick master fixed that problem.

    Comment


    • #3
      was going to say possibly clutch issue or clutch pedal hydraulic. I old days, if you couldn't get into gear a simple clutch linkage adjustment would usually work ( not enough clutch movement with pedal depressed).
      When in doubt, Whip it out !

      Comment


      • #4
        I'm no expert but I was thinking hydraulics or clutch as well. Sent from my Pixel XL using Tapatalk

        Comment


        • #5
          Clutch is an LS7 that was in the car when I bought it 6.5 years ago. I've run it suspended on the lift, clutch in, 1st gear, revving and the wheels don't turn. I'm thinking it's a synchro issue. While rolling to a stop, I can't get the stick to go into 1st or 2nd.
          Last edited by Lucky SOB; April 13th, 2017, 07:32 PM.
          2000 Trans Am l 1967 Firebird

          sigpic

          Comment


          • #6
            How high are you revving it, while checking for movement? Take that ***** to redline. My guess is the clutch isn't disengaging. Which leads to hydraulics, did you measure air-gap? What master cylinder?
            2000 Formula
            fixed slow junk

            Comment


            • #7
              Was also going to suggest clutch not fully disengaging. Does the car feel like it tries to roll forward just a tad when you are able to engage first gear with the car idling?

              Comment


              • #8
                I've revved it to about 4k and no movement, but I'll try again tomorrow. What air gap do I measure? Never done this, let alone heard of it. It has the stock master cylinder. Sent from my iPhone using Tapatalk
                2000 Trans Am l 1967 Firebird

                sigpic

                Comment


                • #9
                  with the clutch pushed in, measure the gap between the disc and the pressure plate. Also, have somebody push in the clutch while you look for firewall flexing.
                  When in doubt, Whip it out !

                  Comment


                  • #10
                    Revved the crap out of it. No wheel movement. So I pulled the trans out. What is the dimension or range that I'm looking for in this clutch measurement now that I have the trans out of the way? Sent from my iPhone using Tapatalk
                    2000 Trans Am l 1967 Firebird

                    sigpic

                    Comment


                    • #11
                      Probably in the .040-.075 range
                      When in doubt, Whip it out !

                      Comment


                      • #12
                        But now with the trans out you can't check it
                        When in doubt, Whip it out !

                        Comment


                        • #13
                          This has to be checked with the trans out. https://ls1tech.com/forums/manual-tr...need-shim.html

                          2000 Formula
                          fixed slow junk

                          Comment


                          • #14
                            I was talking about pushing in the clutch and measuring distance between disc and pressure plate.
                            When in doubt, Whip it out !

                            Comment


                            • #15
                              Lucky SOB , where are you working on this? Can I stop by and take a look? I want to make sure I don't end up in the same boat when I do a new clutch and hydraulics for my car. I think you have my cell & text number, please text me and let me know.

                              "PETA = People Eating Tasty Animals" -- 1977z28Will

                              Comment

                              Working...
                              X