M6 grinding issues
Thread Starter
Launching!
Joined: Dec 2006
Posts: 222
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From: upstate ny
M6 grinding issues My car has almost 80k miles on it now and I've just recently noticed a 1-2 grind. Sometimes it won't do it all but most of the time when it does it is when I'm getting on it in 1st and grab 2nd really fast. I still have the original clutch in the car which will be replaced in the spring. There is no pressure on the pedal until I have pushed it half way down which could be a hydraulic issue perhaps? So i was thinking maybe this is causing the grinding, but I haven't noticed it in other gears. I also will change the transmission fluid in the spring which I'm not sure if that has ever been done which probably isn't good 
. So after doing some research on here I've kind of gathered that a synchro is causing my problems. I just thought I would post all the details in case it could be something else (I hope). I don't have any experience with rebuilding a transmission so what would be a ballpark price for labor and parts for a rebuild, do you think I'll need to replace any gears? I guess I really won't know until its apart, but I would appreciate past experiences and advice from other people. Even with 80k overall the car is still in great shape and the motor still seems to run really strong 
BTW nothing will be done to the car until spring since its put away for the winter. Thanks for taking the time to read my long winded post.
. So after doing some research on here I've kind of gathered that a synchro is causing my problems. I just thought I would post all the details in case it could be something else (I hope). I don't have any experience with rebuilding a transmission so what would be a ballpark price for labor and parts for a rebuild, do you think I'll need to replace any gears? I guess I really won't know until its apart, but I would appreciate past experiences and advice from other people. Even with 80k overall the car is still in great shape and the motor still seems to run really strong BTW nothing will be done to the car until spring since its put away for the winter. Thanks for taking the time to read my long winded post. like many others say if 1-2 gear issues most likely internal... you threw in there that clutch won't engage till halfway down that shouldn't be an issue since it is still engaging but if you have air in the system it could delay it, does it have a spongie feel to the clutch? and ballpark price i just paid 1000 to have my tranny rebuilt 5th gear and slider were screwed up so it bumped the price up to 1300 just to give you a ballpark price... to tell you the truth if mine wasn't a daily driver i would have held out for an mn12 from a gto i heard the gearing is more aggresive and around the same price range for a rebuild if you find a good deal
Thread Starter
Launching!
Joined: Dec 2006
Posts: 222
Likes: 0
From: upstate ny
like many others say if 1-2 gear issues most likely internal... you threw in there that clutch won't engage till halfway down that shouldn't be an issue since it is still engaging but if you have air in the system it could delay it, does it have a spongie feel to the clutch? and ballpark price i just paid 1000 to have my tranny rebuilt 5th gear and slider were screwed up so it bumped the price up to 1300 just to give you a ballpark price... to tell you the truth if mine wasn't a daily driver i would have held out for an mn12 from a gto i heard the gearing is more aggresive and around the same price range for a rebuild if you find a good deal
if you have headers there are instances where the master cylinders line is close to them and the fluid begins to boil... causing air in the system which would give you a spongie feel, or you introduced water into the system somehow (which is easy to do if you leave the cap off for a while as brake fluid is hydroscopic? which means it absorbs water very easily) making the boiling point of the brake fluid drop which makes it easier to boil with headers... but if it were your clutch it would be present in all gears... if you have an adjustable master cylinder you might have to adjust the pushrod or the pedal height if you are stock to fix the pedal issue... but as far as grinding goes i'm pretty sure it would be internal
mines doing the same thing its a 98 formula and i just got an LS7 clutch kit out in....wastn doing it before hand but i do have a feeling that i managed to bend the shift fork when the stock clutch went...but i have bled the sytem many times and also drianed the fluid so i dont believe that would be the issue....it is going to be internal so i am just dealing with it until i can find a built trans or get a DD so i can send mine out and get rebuilt....money is just wayyyy to tight right now for anything so best advice i can give is be gentle until u can get it rebuilt....good luck
you know sometimes just because it doesn't grind doesn't mean it isn't causing damage... my fifth gear wouldn't go in if i downshifted but it never grinded when shifting up and even when it spit it out toward the end before the rebuild it didn't grind came out and the fifth gear edges were chewed up as well as the slider's teeth but luckily with manuals it sticks to one gear and usually doesn't grenade the tranny like automatics... i think my fifth gear came out to almost two hundred bucks
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Verdad Gallardo i've heard good things about TICK i believe and the sponsor seems to be very helpful to all... but don't go spending money on a rebuild unless you get the problem down precisely
Last edited by beezer1519; Nov 19, 2008 at 08:27 PM.
mine did the same damn thing until i pulled it and sent it to Joey at TICK PERFORMANCE....great guy cant say enough about customer serive ...down to earth..not one of those snobby * yes yes we know it all* people...less than $1300 shipped back and forth including rebuild/ new bearings and a stage 2 build..but i got it on a special...have to say tho that tranny has survived some sht so far..and its just laughin at me...damn good people/ damn good service/and a damn good product...you wont be dissapointed..hell i am half tempted to offer you a refund from my pocket if you dont like their work....yes i am THAT CONFIDENT
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Teching In
Joined: Nov 2007
Posts: 2
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try this just my 2 cents here. i have the same problem trying to cram into second gear at 6k rpms and it will grind just because the time it takes for the fluid to actually push on the pressure plate. it's not an internal problem, the reason it only happeneds in 1st to 2nd is the simple fact that you probly arent hitting 6k rpm in 2nd gear trying to shift into 3rd the same way because its to fast unless your on the strip and you dont want to get your car impounded. From what ive heard GM engineered the hydro line to cause the restriction so we didnt shift into gear at high rpms so we dont brake the shotty rear ends. you can drill the end of the line out with a 3/8ths bit i believe it was and that seems to help flow or just get an adjustable master to get better response on the clutching try these first its alot cheaper and im pretty sure your going to see your results. Thats what i got for ya good luck!