Will not shift over 5,000 rpm - LS1-T-56
#1
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As the title states. We bought a used 2001 Z28 to go CMC racing. Car will not shift over 5,000 rpm's, especially 3rd to 4th and 4th to 5th. At our last track day, I also had a problem with the car going into first gear sitting still, and later in the day it would not go into reverse sitting still.
We started out thinking the line may be getting hot, so we moved and insulated it. Then we thought maybe the throwout bearing was bad, so we put a new GM in. No change. We have put a remote bleeder on and have bled the system multiple times.
There is no grinding, it's just like it won't go past the gate into gear, like the clutch is not disengaging. Our air gap is good. Thought maybe the clutch was bad even though the discs looked brand new. The pressure plate and flywheel are both concaved a bit, I thought it was due to warpage from heat. So I ordered a new LS6 clutch setup from GM and damn, the new one is the exact same, so that's not my problem.
About the only thing left to look at that I can think of is the master cylinder.
Has anyone had this problem or does anyone have any ideas? I have the tranny out again right now and I do NOT want to lose another day at the track and have to pull it again. Thanks for any assistance you can offer!
We started out thinking the line may be getting hot, so we moved and insulated it. Then we thought maybe the throwout bearing was bad, so we put a new GM in. No change. We have put a remote bleeder on and have bled the system multiple times.
There is no grinding, it's just like it won't go past the gate into gear, like the clutch is not disengaging. Our air gap is good. Thought maybe the clutch was bad even though the discs looked brand new. The pressure plate and flywheel are both concaved a bit, I thought it was due to warpage from heat. So I ordered a new LS6 clutch setup from GM and damn, the new one is the exact same, so that's not my problem.
About the only thing left to look at that I can think of is the master cylinder.
Has anyone had this problem or does anyone have any ideas? I have the tranny out again right now and I do NOT want to lose another day at the track and have to pull it again. Thanks for any assistance you can offer!
#2
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Wish you would have posted here before you went and changed the clutch. The fact that it would disengage when it sits still really points to the mc rather than the clutch. The eom mic is crap and is barely capable of disengaging the clutch in day to day driving. Go with a tick unit and be problem free
#3
FormerVendor
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As the title states. We bought a used 2001 Z28 to go CMC racing. Car will not shift over 5,000 rpm's, especially 3rd to 4th and 4th to 5th. At our last track day, I also had a problem with the car going into first gear sitting still, and later in the day it would not go into reverse sitting still.
We started out thinking the line may be getting hot, so we moved and insulated it. Then we thought maybe the throwout bearing was bad, so we put a new GM in. No change. We have put a remote bleeder on and have bled the system multiple times.
There is no grinding, it's just like it won't go past the gate into gear, like the clutch is not disengaging. Our air gap is good. Thought maybe the clutch was bad even though the discs looked brand new. The pressure plate and flywheel are both concaved a bit, I thought it was due to warpage from heat. So I ordered a new LS6 clutch setup from GM and damn, the new one is the exact same, so that's not my problem.
About the only thing left to look at that I can think of is the master cylinder.
Has anyone had this problem or does anyone have any ideas? I have the tranny out again right now and I do NOT want to lose another day at the track and have to pull it again. Thanks for any assistance you can offer!
We started out thinking the line may be getting hot, so we moved and insulated it. Then we thought maybe the throwout bearing was bad, so we put a new GM in. No change. We have put a remote bleeder on and have bled the system multiple times.
There is no grinding, it's just like it won't go past the gate into gear, like the clutch is not disengaging. Our air gap is good. Thought maybe the clutch was bad even though the discs looked brand new. The pressure plate and flywheel are both concaved a bit, I thought it was due to warpage from heat. So I ordered a new LS6 clutch setup from GM and damn, the new one is the exact same, so that's not my problem.
About the only thing left to look at that I can think of is the master cylinder.
Has anyone had this problem or does anyone have any ideas? I have the tranny out again right now and I do NOT want to lose another day at the track and have to pull it again. Thanks for any assistance you can offer!
#4
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Wish you would have posted here before you went and changed the clutch. The fact that it would disengage when it sits still really points to the mc rather than the clutch. The eom mic is crap and is barely capable of disengaging the clutch in day to day driving. Go with a tick unit and be problem free
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For fluid we are using a Wilwood EXP 600 Plus brake fluid.
We have to run OEM or OEM equivalent clutch.