[Z06] Tranny Gone
Safety Car
Joined: Sep 2001
Posts: 4,596
Likes: 2
From: Atlanta GA
Re: Tranny Gone (Roc Con)
I have an 02 that just started grinding when I try to go into 4th. I can downshift from 5th into 4th with no problem but no good on the 3-4. Also at highway speeds (50-60) it will no longer let me downshift into 3rd. Does this sound like the syncro problem you guys are experiencing? Also should I take out the Hurst & install the stock shifter before going to the dealer?
Thread Starter
Drifting
Joined: Nov 2001
Posts: 1,684
Likes: 0
From: Jacksonville Florida
Re: Tranny Gone (Roc Con)
Definitely sounds like a syncro. Some dealers are not mod friendly like gmblack3 says so be careful. Find out if others with an aftermarket shifter have had warranty denied. Most dealers and mechanics understand that this problem is not caused my mods, but best to be careful.
Les
Les
I have an 02 that just started grinding when I try to go into 4th. I can downshift from 5th into 4th with no problem but no good on the 3-4. Also at highway speeds (50-60) it will no longer let me downshift into 3rd. Does this sound like the syncro problem you guys are experiencing? Also should I take out the Hurst & install the stock shifter before going to the dealer?
Intermediate
Joined: Jan 2000
Posts: 34
Likes: 0
From: Tucson AZ
Re: Tranny Gone (ZO6Les)
Wow! This sounds horrible. I traded my 99 FRC for an 03 Z last weekend. My 99 shifted very slick and smooth. The Z feels much notchier. I have noticed that it takes a little more finese (blipping the throttle) on down shifts for a smooth transition between gears on my Z. Don't know if this is an early symptom of what you guys are seeing or if it's just that's everything is new and not broken in yet. Car only has 255 miles so far. I can't remember my 99 being like this but, that was 4 years ago and you know what they say about memory being the first thing to go :lol:
Thread Starter
Drifting
Joined: Nov 2001
Posts: 1,684
Likes: 0
From: Jacksonville Florida
Re: Tranny Gone (hrdtop)
I find the M12 tranny shifts extremely well right up to the point that it breaks. Not all of them do break, in fact most do not. But lately there has been quite a few of us having syncro problems and/or clutch problems - makes one go hmmm.
Enjoy that notchy solid feel when you shift - it is made that way :)
Les :cheers:
Enjoy that notchy solid feel when you shift - it is made that way :)
Les :cheers:
Wow! This sounds horrible. I traded my 99 FRC for an 03 Z last weekend. My 99 shifted very slick and smooth. The Z feels much notchier. I have noticed that it takes a little more finese (blipping the throttle) on down shifts for a smooth transition between gears on my Z. Don't know if this is an early symptom of what you guys are seeing or if it's just that's everything is new and not broken in yet. Car only has 255 miles so far. I can't remember my 99 being like this but, that was 4 years ago and you know what they say about memory being the first thing to go :lol:
Intermediate
Joined: Jan 2000
Posts: 34
Likes: 0
From: Tucson AZ
Re: Tranny Gone (ZO6Les)
I am enjoying it so far! :D It's pretty tough to resist getting aggressive with the car until I get 500 miles on it though... ;)
I find the M12 tranny shifts extremely well right up to the point that it breaks. Not all of them do break, in fact most do not. But lately there has been quite a few of us having syncro problems and/or clutch problems - makes one go hmmm.
Enjoy that notchy solid feel when you shift - it is made that way :)
Les :cheers:
Enjoy that notchy solid feel when you shift - it is made that way :)
Les :cheers:
Former Vendor
Joined: Apr 2001
Posts: 2,719
Likes: 3
From: Anderson Indiana
Re: Tranny Gone (hrdtop)
I happen to offer several upgrades for the M6's and M12's.Tremec made improvements on all C5 units on the 1st/2nd synchro keys because of the added pressure they recieve from the 3 coned synchronizers,but they kept the VERY weak keys on 3rd/4th which results in about 90% of the failures you guys are having.I have spent many hours coming up with durability improvements for the T56.I currently have solid Billet keys and special springs made to help solve this issue and recommend the Steel Fork that I use in all of my units.I will be happy to provide pics of these upgrades to anyone interested.If your transmission is replaced under warranty do EVERYTHING to try and keep youer old one and send it to me for the upgrades for a spare. :thumbs:
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Drifting
Joined: Oct 1999
Posts: 1,272
Likes: 0
From: Gaithersburg MD
Cruise-In II Veteran
Cruise-In III Veteran
Re: Tranny Gone (Roc Con)
Roc Con, your symptoms are the same as mine. It will only get worse.
I took mine to the dealer with the Hurst installed. They checked for rubber in the wheel wells and found none. They are replacing all the Syncro's plus other pieces as needed. I watched the mechanic take the trans apart and will post pic's later this week. All the gears etc., looked good. However, there was what looked like little bits of black paper floating in the trans fluid. A lot of it. I assume it was pieces of the syncro cones.
Supposed to get it back tomorrow. We will see.
I took mine to the dealer with the Hurst installed. They checked for rubber in the wheel wells and found none. They are replacing all the Syncro's plus other pieces as needed. I watched the mechanic take the trans apart and will post pic's later this week. All the gears etc., looked good. However, there was what looked like little bits of black paper floating in the trans fluid. A lot of it. I assume it was pieces of the syncro cones.
Supposed to get it back tomorrow. We will see.
Drifting
Joined: Oct 2001
Posts: 1,366
Likes: 0
From: America
Re: Tranny Gone (Crashed 94)
Crashed,
Thanks for the reply....I do feel somewhat vindicated now......... :thumbs:
This problem reared it's UGLY head DAY 1, of '02's hitting the streets....
We KNOW that Tremec SUPPOSEDLY upgraded the syncros.........
From '01's to '02's......( this came from a very well known C5Tech).
The parts used in the T56, for 3-4, are not tough enough to take the use they see with these cars..and neither are the aluminum shift forks....
please post pic's, of current use, and upgrad parts IF possible...if not, IM me, Iwill give you my E Mail...
Thanks a lot........you made my day. :D
Thanks for the reply....I do feel somewhat vindicated now......... :thumbs:
This problem reared it's UGLY head DAY 1, of '02's hitting the streets....
We KNOW that Tremec SUPPOSEDLY upgraded the syncros.........
From '01's to '02's......( this came from a very well known C5Tech).
The parts used in the T56, for 3-4, are not tough enough to take the use they see with these cars..and neither are the aluminum shift forks....
please post pic's, of current use, and upgrad parts IF possible...if not, IM me, Iwill give you my E Mail...
Thanks a lot........you made my day. :D
Race Director
Joined: Dec 2000
Posts: 14,581
Likes: 10
From: City of Turbo Buicks in Corvette County FL
Re: Tranny Gone (ZO6LS6)
There may be a new fix from GM.
I got my Z06 back last thursday. Usually, it was the key problem. This time the mechanics called tech support for these trannies and they got some new parts last week. They said there was a new TSB. Last time I was there was about a month ago for hte same problem. They said these new parts aren't even listed yet, and a price isn't even available. I asked my service rep to send me some more info about this new part that should fix the problem. So far it is working nicely.
Anyone here about a new TSB on getting stuck in 4th?
I got my Z06 back last thursday. Usually, it was the key problem. This time the mechanics called tech support for these trannies and they got some new parts last week. They said there was a new TSB. Last time I was there was about a month ago for hte same problem. They said these new parts aren't even listed yet, and a price isn't even available. I asked my service rep to send me some more info about this new part that should fix the problem. So far it is working nicely.
Anyone here about a new TSB on getting stuck in 4th?
Drifting
Joined: Oct 1999
Posts: 1,272
Likes: 0
From: Gaithersburg MD
Cruise-In II Veteran
Cruise-In III Veteran
Re: Tranny Gone (ZO6LS6)
Steve, did you get the steel forks??....and NEW upgrades on the syncro's??
I bought the 3rd - 4th steel shift fork from D & D Performance. I would like to know more about it though. I gave it to the mechanic to install if he feels comfortable doing that. This work is being done under warranty. After seeing the stock aluminum forks compared to the steel one, I can see why he expressed some reservations about installing it. While the important spots seem to be all in the right spots, the steel fork is much slimmer and different in many respects. Again, I plan on posting pic's for everyone to see.
I am unaware of any "new" syncro's, other than the so called upgrade on the M12 compared to the M6 trans. Do you have any part numbers?
I bought the 3rd - 4th steel shift fork from D & D Performance. I would like to know more about it though. I gave it to the mechanic to install if he feels comfortable doing that. This work is being done under warranty. After seeing the stock aluminum forks compared to the steel one, I can see why he expressed some reservations about installing it. While the important spots seem to be all in the right spots, the steel fork is much slimmer and different in many respects. Again, I plan on posting pic's for everyone to see.
I am unaware of any "new" syncro's, other than the so called upgrade on the M12 compared to the M6 trans. Do you have any part numbers?
Drifting
Joined: Oct 2001
Posts: 1,366
Likes: 0
From: America
Re: Tranny Gone (Steve Row)
Steve,
No, I was talking about ones from someone like Crashed '94, I figure we will get ONE freebie shot at this, and then the ball game will be on us...
On the shift fork.....what was the reasoning for NOT doing the swap?.
Did the Tech think it would not operate correctly..and din't want to try it and it not work after install??.
The upgrade( black floating crap)....was supposed to be stronger than the '01's..
The supposedly went to a COMPRESSED carbon fiber material on the '02's, as compared to the COMPRESSED paper '01's........
Personally, I never saw a 1/10th as many posts about '01 trannies....compared to '02's.........
Crummy shifters, yeah buddy...but, very few trannie failures........ :nonod:
No, I was talking about ones from someone like Crashed '94, I figure we will get ONE freebie shot at this, and then the ball game will be on us...
On the shift fork.....what was the reasoning for NOT doing the swap?.
Did the Tech think it would not operate correctly..and din't want to try it and it not work after install??.
The upgrade( black floating crap)....was supposed to be stronger than the '01's..
The supposedly went to a COMPRESSED carbon fiber material on the '02's, as compared to the COMPRESSED paper '01's........
Personally, I never saw a 1/10th as many posts about '01 trannies....compared to '02's.........
Crummy shifters, yeah buddy...but, very few trannie failures........ :nonod:
Former Vendor
Joined: Apr 2001
Posts: 2,719
Likes: 3
From: Anderson Indiana
Re: Tranny Gone (ZO6LS6)
The synchronizer acts as a brake on the faster spinning gear to stop it before the slider engages with the engagement teeth on that gear,so Tremec designed a 3 piece synchronizer exclusive for the C5 transmission.The 3 piece design has superior stopping power on the gear but the three very weak keys will shear off and the entire synchronizer will just spin with the gear causing the slider and gear to Grind before engagement.The keys also act as the detents between the gears and when they break they will cause the slider to hang up and end up stuck in one gear.I honestly believe that a major problem is in the clutch/slave set-up,The clutch is not getting fully released under hard acceleration and high RPM's and destroying these transmissions.
Former Vendor
Joined: Apr 2001
Posts: 2,719
Likes: 3
From: Anderson Indiana
Re: Tranny Gone (Crashed 94)
Steel forks should be a must!!! The Factory aluminum forks don't bend like you would think,but they actually wear where they are attached to the steel arm that attaches them to the shift rail, creating slop between the fork and the arm.When the aluminum compresses and gets smashed out it will not allow the slider to fully engage the gear and cause the gear to pop out.At least make the dealer install a new Aluminum fork while it is apart if they won't go for the steel fork,this is an easy overlooked item that will cause a lot of griefs later.
[Modified by Crashed 94, 11:00 PM 11/24/2002]
[Modified by Crashed 94, 11:00 PM 11/24/2002]
[Modified by Crashed 94, 11:00 PM 11/24/2002]
[Modified by Crashed 94, 11:00 PM 11/24/2002]
Drifting
Joined: Oct 1999
Posts: 1,272
Likes: 0
From: Gaithersburg MD
Cruise-In II Veteran
Cruise-In III Veteran
Re: Tranny Gone (ZO6LS6)
Z06LS6,
The mechanic and shop foremen are reluctant to install anything other than genuine GM parts under warranty. If something fails, they have to fix it out of pocket unless they use GM parts. Since they are not familiar with the steel forks and the fork looks quite different, they are not too keen on the idea.
Somehow, Tremec missed the boat on the "upgrade". I had a 2000 Coupe and never had a problem with shifting.
Crashed 94, you have mail.
[Modified by Steve Row, 8:14 AM 11/25/2002]
The mechanic and shop foremen are reluctant to install anything other than genuine GM parts under warranty. If something fails, they have to fix it out of pocket unless they use GM parts. Since they are not familiar with the steel forks and the fork looks quite different, they are not too keen on the idea.
Somehow, Tremec missed the boat on the "upgrade". I had a 2000 Coupe and never had a problem with shifting.
Crashed 94, you have mail.
[Modified by Steve Row, 8:14 AM 11/25/2002]
Thread Starter
Drifting
Joined: Nov 2001
Posts: 1,684
Likes: 0
From: Jacksonville Florida
Re: Tranny Gone (Crashed 94)
I believe you have hit the nail on the head. Short of an aftermarket clutch it would seem the general can only keep replacing the stock clutches and tranny's??
Les
Les
The synchronizer acts as a brake on the faster spinning gear to stop it before the slider engages with the engagement teeth on that gear,so Tremec designed a 3 piece synchronizer exclusive for the C5 transmission.The 3 piece design has superior stopping power on the gear but the three very weak keys will shear off and the entire synchronizer will just spin with the gear causing the slider and gear to Grind before engagement.The keys also act as the detents between the gears and when they break they will cause the slider to hang up and end up stuck in one gear.I honestly believe that a major problem is in the clutch/slave set-up,The clutch is not getting fully released under hard acceleration and high RPM's and destroying these transmissions.
Drifting
Joined: Oct 1999
Posts: 1,272
Likes: 0
From: Gaithersburg MD
Cruise-In II Veteran
Cruise-In III Veteran
Re: Tranny Gone (Crashed 94)
Crashed 94, thanks for your post.
Called the mechanic about the steel shift fork. Read him Crashed 94's comments about the shift fork getting sloppy on the shaft. He called me back about an hour later to tell me that he went back and looked for that and found it. the shift fork was very sloppy on the shaft.
:yesnod:
Called the mechanic about the steel shift fork. Read him Crashed 94's comments about the shift fork getting sloppy on the shaft. He called me back about an hour later to tell me that he went back and looked for that and found it. the shift fork was very sloppy on the shaft.
:yesnod:
Former Vendor
Joined: Apr 2001
Posts: 2,719
Likes: 3
From: Anderson Indiana
Re: Tranny Gone (Steve Row)
I've been there ,Done That. :eek: Guys when these cars are out of warranty or you've had enough with the dealers and stock parts feel free to look me up for your transmission and rear differential needs. :thumbs: