GM made better trannies in July 02! Tell me if this is true.
10-23-2003, 03:36 PM
#1
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GM made better trannies in July 02! Tell me if this is true. Ok I "heard" GM started making stronger transmissions after July 02 that came with stronger steel shiftforks and stronger bearings (dont know if anything else was upgraded). Anyone know if this is true?
my tranny came down 2 days ago and it I got a new one under warranty going in as we speak.
Service guy claimed the tranny going in has the part number is 12561561.
Just want to know I am getting the better tranny.
If the whole story about GM making stronger trannies is BS let me know.
Thanks.
my tranny came down 2 days ago and it I got a new one under warranty going in as we speak.
Service guy claimed the tranny going in has the part number is 12561561.
Just want to know I am getting the better tranny.
If the whole story about GM making stronger trannies is BS let me know.
Thanks.
10-23-2003, 04:20 PM
#2
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Re: GM made better trannies in July 02! Tell me if this is true. Z06's got steel shift forks and some other upgraded parts, but I thought that was during late '03.
10-27-2003, 02:43 AM
#3
Well I was the guy you "heard" it from 
Update the service manager couldn't gaurantee the upgraded tranny which if the gentleman above is correct is a Corvette tranny anyways... So they ordered all the parts which are all parts of TSB's .....for instance if your tranny is popping out of third they replace it with the Iron shift fork.. if your tranny is grinding they replace the paper with the carbon syncro's etc. Basically they are saying my tranny has ALL the TSB problems HOPEFULLY while they are at it they will fix the "mystery gear" problem.
I think they came in F-bodys towards the end of production. He asked me to make a SPECIAL trip to get the serial number off mine to make sure it wasn't one of the newer ones already. Don't know why the GM employed T56 help line would want that if it wasn't a possibility....
Just my experience, my dealer could be full of BS as well I can't stand that place
Of course they don't care for me too much either
Update the service manager couldn't gaurantee the upgraded tranny which if the gentleman above is correct is a Corvette tranny anyways... So they ordered all the parts which are all parts of TSB's .....for instance if your tranny is popping out of third they replace it with the Iron shift fork.. if your tranny is grinding they replace the paper with the carbon syncro's etc. Basically they are saying my tranny has ALL the TSB problems HOPEFULLY while they are at it they will fix the "mystery gear" problem.I think they came in F-bodys towards the end of production. He asked me to make a SPECIAL trip to get the serial number off mine to make sure it wasn't one of the newer ones already. Don't know why the GM employed T56 help line would want that if it wasn't a possibility....
Just my experience, my dealer could be full of BS as well I can't stand that place
Of course they don't care for me too much either 
10-27-2003, 11:49 PM
#7
Originally Posted by 93TAWicked1
Well I was the guy you "heard" it from Update the service manager couldn't gaurantee the upgraded tranny which if the gentleman above is correct is a Corvette tranny anyways... So they ordered all the parts which are all parts of TSB's .....for instance if your tranny is popping out of third they replace it with the Iron shift fork.. if your tranny is grinding they replace the paper with the carbon syncro's etc. Basically they are saying my tranny has ALL the TSB problems HOPEFULLY while they are at it they will fix the "mystery gear" problem.
I think they came in F-bodys towards the end of production.
Update the service manager couldn't gaurantee the upgraded tranny which if the gentleman above is correct is a Corvette tranny anyways... So they ordered all the parts which are all parts of TSB's .....for instance if your tranny is popping out of third they replace it with the Iron shift fork.. if your tranny is grinding they replace the paper with the carbon syncro's etc. Basically they are saying my tranny has ALL the TSB problems HOPEFULLY while they are at it they will fix the "mystery gear" problem.I think they came in F-bodys towards the end of production.
The carbon fibre synchro linings were in 2001 and 2002 f-bodies anyway. Tremec services all f-body 6 speeds with carbon fibre; you aren't getting anything special; those are just normal service parts.
As far as the steel fork, I do not know of any 02 f-bodies getting them. It's such a popular part, I wonder if they even sell the aluminum fork anymore.
For all the "my forks are bent
" posts you'll see, 99% of them are misdiagnosis & the problem is improperly releasing hydraulics which fragged the synchros; NOT a bent fork. Look at how healthy that fork is and IIRC, it's larger than 1-2 or 5-6.There isn't anything wrong with the fibre linings used from 1988 through 2000; they last. However, you can't use synchromesh with them.
matthew
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10-28-2003, 12:21 AM
#8
Hmm yeah I have a big concern that after this third round of tranny tearing apart I'm still going to have the problem with it not letting it into third gear sometimes
Matthew sounds pretty up to date on it guess my dealer is just blowing more smoke up my ***, cause they can't figure out how to fix my tranny. They look at me like I'm crazy VERY FRUSTRATING!
Matthew sounds pretty up to date on it guess my dealer is just blowing more smoke up my ***, cause they can't figure out how to fix my tranny. They look at me like I'm crazy
VERY FRUSTRATING! 
11-01-2003, 11:27 AM
#11
Originally Posted by SSCamaro99_3
Please, tell me you are kidding. I have Synchrmesh in my 99 right now.
11-01-2003, 11:28 AM
#12
Originally Posted by jmd
I thought that the synchromesh GM sold was gear oil based. You can't run gear oil (like 80-90W) with the fibre synchros becuase it will swell them. Maybe there is a 2nd type of synchromesh or I was misinformed on the synchromesh.
03-22-2004, 12:22 AM
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Dunno if this will matter or not to anyone, but I just used the synthetic blend DexIII in mine, course that was 20K miles ago and now I'm having to take it back apart and put in a set of custom made solid keeper keys.
01-03-2005, 01:45 PM
#15
NEVER PUT SYNCRHOMESH IN ANY T-56 TRANNY!!!!!! They are designed for Dexron III AUTOMATIC TRANS FLUID ONLY!!!!! Anyone with synchromesh in their trans should change it immediately and pray their synchros last another 10k miles!!!!!
Synchromesh is for some front-drive manuals and maybe some Geo Tracker manuals. NEVER in corvette or Camaro applications!!!
Furthermore, the only other fluid you can use is a newer transfer case fluid called "Auto-Trac II" fluid use to fix transfer case internal clutch problems on 4WD vehicles. This is basically a synthetic auto fluid but should never be used in an auto tranny. It will need to be changed more often however cause I've heard it gets dirty easier then regular ATF. Should shift better in sub-40 degree temps with this fluid.
Synchromesh is for some front-drive manuals and maybe some Geo Tracker manuals. NEVER in corvette or Camaro applications!!!
Furthermore, the only other fluid you can use is a newer transfer case fluid called "Auto-Trac II" fluid use to fix transfer case internal clutch problems on 4WD vehicles. This is basically a synthetic auto fluid but should never be used in an auto tranny. It will need to be changed more often however cause I've heard it gets dirty easier then regular ATF. Should shift better in sub-40 degree temps with this fluid.
01-04-2005, 11:52 AM
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Originally Posted by SSblack98
NEVER PUT SYNCRHOMESH IN ANY T-56 TRANNY!!!!!! They are designed for Dexron III AUTOMATIC TRANS FLUID ONLY!!!!! Anyone with synchromesh in their trans should change it immediately and pray their synchros last another 10k miles!!!!!
Synchromesh is for some front-drive manuals and maybe some Geo Tracker manuals. NEVER in corvette or Camaro applications!!!
Furthermore, the only other fluid you can use is a newer transfer case fluid called "Auto-Trac II" fluid use to fix transfer case internal clutch problems on 4WD vehicles. This is basically a synthetic auto fluid but should never be used in an auto tranny. It will need to be changed more often however cause I've heard it gets dirty easier then regular ATF. Should shift better in sub-40 degree temps with this fluid.
Synchromesh is for some front-drive manuals and maybe some Geo Tracker manuals. NEVER in corvette or Camaro applications!!!
Furthermore, the only other fluid you can use is a newer transfer case fluid called "Auto-Trac II" fluid use to fix transfer case internal clutch problems on 4WD vehicles. This is basically a synthetic auto fluid but should never be used in an auto tranny. It will need to be changed more often however cause I've heard it gets dirty easier then regular ATF. Should shift better in sub-40 degree temps with this fluid.
01-04-2005, 06:16 PM
#18
Synchromesh is for just about any manual transmission requireing manual transmission fluid HOWEVER we know the T56 requires auto trans fluid (lol though my auto parts store guy almost refused to sell me auto trans fluid when I told him I was changing the fluid in a manual trans). This is why I've been heasitant to run synchromesh in my T/A. I have it in my blazer's 5 speed, and it works great though!
01-04-2005, 07:06 PM
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synchromesh is for manuals that use automatic fluid. Any old gearbox like a Muncie would destroy itself in a second with this stuff, its too thin.
I have been running synchromesh with NO PROBLEMS.
I have been running synchromesh with NO PROBLEMS.
