2nd gear synchro issue?????
09-27-2014, 08:55 PM
#1
2nd gear synchro issue?????
I have a 2014 Z51 M7. recently, I have had trouble shifting from first to second, especially when cold. sometimes I have to force it into gear, and sometimes it grinds before it meshes.
yes - I know about 1-4 skip shift. I have the skip shift eliminator.
yes - I checked the forum. searched several keywords. couldn't find any similar threads.
no - this is not my first manual transmission car. in fact, my first manual transmission car had a Moss crashbox. if you can shift that, you can shift anything.
took it to the dealer. technician said there has been some reported problems with the internal shift mechanism. he contacted GM engineering and they told him that this was an issue and that they would get back to him. they told him not to do anything to the car before they got back to him.
I am driving the car, and being very dainty with my 1-2 and 3-2 shifts, until I hear from my technician.
anyone else experienced this problem? was it solved? what was the cure?
thanks
yes - I know about 1-4 skip shift. I have the skip shift eliminator.
yes - I checked the forum. searched several keywords. couldn't find any similar threads.
no - this is not my first manual transmission car. in fact, my first manual transmission car had a Moss crashbox. if you can shift that, you can shift anything.
took it to the dealer. technician said there has been some reported problems with the internal shift mechanism. he contacted GM engineering and they told him that this was an issue and that they would get back to him. they told him not to do anything to the car before they got back to him.
I am driving the car, and being very dainty with my 1-2 and 3-2 shifts, until I hear from my technician.
anyone else experienced this problem? was it solved? what was the cure?
thanks
09-27-2014, 09:00 PM
#2
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St. Jude Donor '11-'12-'13, '16-'17-'18
Haven't had a problem with mine (2014, Z51, VIN 11822) other than shifting is a little....chunky? when cold but smooths right out when it warms up a bit - usually a few miles in 70 degree weather is enough
09-27-2014, 09:01 PM
#3
Le Mans Master
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My 1 to 2 is also difficult. Took it to the dealer. Dealer said it was normal. 
09-27-2014, 09:26 PM
#4
Moderator
Yes, I have exactly the same issue. I have not taken it to the dealer yet. I assume that it is a 1-2 synchro issue since it does not occur on any other gear change. I do NOT have the same issue going into 2nd when downshifting. Only 1-2 and only sometimes. I have tried to identify a pattern as to when it happens, but it seems totally random. The sometimes clunky shifting when cold is one thing, but the grinding when attempted to go into 2nd is not good.
09-27-2014, 09:37 PM
#5
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Sounds like proper diag to me. Usually shifting gets hard, then grinding, then when the synchro is just shot and you shift in the second you will just get a solid CLINK sound. happens to Honda's manual trans third gear on almost all cars that kids are "racing".. Lol
09-27-2014, 10:45 PM
#6
glad to know it's not only me.
my technician (he is also a friend of 15 years and I trust him completely) will contact me as soon as he hears from the GM engineers.
perhaps if we all refused to accept this condition and just assuming it was normal, especially since GM engineers acknowledge it is a problem they have yet to solve, and reported the issue to our dealers, GM would accelerate their efforts to find a solution. and maybe not. but it's worth a try, IMHO.
my technician (he is also a friend of 15 years and I trust him completely) will contact me as soon as he hears from the GM engineers.
perhaps if we all refused to accept this condition and just assuming it was normal, especially since GM engineers acknowledge it is a problem they have yet to solve, and reported the issue to our dealers, GM would accelerate their efforts to find a solution. and maybe not. but it's worth a try, IMHO.
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vetehead (12-12-2015)
09-27-2014, 10:52 PM
#7
Team Owner
despite what the rose colored glasses wearing people say, the MN7 isn't the smoothest shifting tranny out there. I've been driving a standards most of my 28 year driving history so I'm fairly confident in my manual driving abilities, not to mention working at a used car dealership or auto industry for the past 20 years and driving many different models with a standard transmission, I can say that the C7 manual isn't the best, sometimes I have to force it into first before I take off at a light and the spacing is tightly packed together. Now I'm not complaining, I'm just saying it isn't buttery smooth as many other transmission, my C5 was much better and that thing lasted me over 100,000 kms and 6 years, never needing a clutch replacement or tranny work at all and it was still going strong the day I sold it.
09-27-2014, 11:00 PM
#8
Mine just comes out of 1st gear on its own when starting from a dead stop when the clutch just engages . I posted yesterday and I am in a Camaro until the issue is fixed. I hear its normal, but im not buying it. I don't know how a gear coming out on its own can be normal unless casper is helping me shift hes doing a **** poor job of it
09-28-2014, 01:02 AM
#9
I have the 1st to 2nd stiffness also. It seems to be a little smoother as the drivetrain warms. I am an early adopter ( #3385 ) and mention the problem back in October but no others responded. Glad it a common issue and maybe a remedy will be available. In the mean time I just kinda double clutch and that helps. I thought at first it might be a clutch problem. Thanks for starting this thread.
09-28-2014, 07:14 AM
#10
Yes, I have exactly the same issue. I have not taken it to the dealer yet. I assume that it is a 1-2 synchro issue since it does not occur on any other gear change. I do NOT have the same issue going into 2nd when downshifting. Only 1-2 and only sometimes. I have tried to identify a pattern as to when it happens, but it seems totally random. The sometimes clunky shifting when cold is one thing, but the grinding when attempted to go into 2nd is not good.
09-28-2014, 08:28 AM
#11
Le Mans Master
Yes I have this issue as well. Mostly when I'm doing wot runs I would say it grinds about 20% of the time at the moment.
It's gonna suck getting repaired I'm gonna have to let some tech flog my car to replicate the issue.
This doesn't suprise me unfortunately this is a GM product after all
It's gonna suck getting repaired I'm gonna have to let some tech flog my car to replicate the issue.
This doesn't suprise me unfortunately this is a GM product after all
09-28-2014, 08:34 AM
#12
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mine was exactlty the same and was FIXED by my dealer a few months ago. The shifter mechanism needed to be adjusted. They had a GM engineer come in and adjust it and it now shifts much smoother in the 1 and 2 gears
Last edited by marktigerz; 09-28-2014 at 08:38 AM.
09-28-2014, 09:13 AM
#14
Race Director
Vin# 22487 has performed flawlessly, transmission is much smoother than my previous 2006 M6 coupe. Even when cold, gear selection is smooth (slightly more feedback as gears mesh) as transmission warms feedback softens, probably oil viscosity change. Really pleased, clutch has smoothed out, (or I have made peace with it) 1,600 miles.
09-28-2014, 10:07 AM
#15
I had the same issue and bought the MGW shifter - fixed the problem.
It's the stock shifter - its just sloppy and lacks precision - after removing and looking at both shifters - the stock has no real adjustments other than moving it on its mounting point, or the plastic cup it sits in on the shift rod..... so if someone is trying to adjust it they are using the lack of precision in the manufacturing of the unit to make the adjustment.
Buy an MGW shifter and you'll be glad you did - I waited for 3 months before I decided to pull the trigger and I am glad I did
It's the stock shifter - its just sloppy and lacks precision - after removing and looking at both shifters - the stock has no real adjustments other than moving it on its mounting point, or the plastic cup it sits in on the shift rod..... so if someone is trying to adjust it they are using the lack of precision in the manufacturing of the unit to make the adjustment.
Buy an MGW shifter and you'll be glad you did - I waited for 3 months before I decided to pull the trigger and I am glad I did
10-31-2014, 04:23 PM
#20
Safety Car
glad to know it's not only me.
my technician (he is also a friend of 15 years and I trust him completely) will contact me as soon as he hears from the GM engineers.
perhaps if we all refused to accept this condition and just assuming it was normal, especially since GM engineers acknowledge it is a problem they have yet to solve, and reported the issue to our dealers, GM would accelerate their efforts to find a solution. and maybe not. but it's worth a try, IMHO.
my technician (he is also a friend of 15 years and I trust him completely) will contact me as soon as he hears from the GM engineers.
perhaps if we all refused to accept this condition and just assuming it was normal, especially since GM engineers acknowledge it is a problem they have yet to solve, and reported the issue to our dealers, GM would accelerate their efforts to find a solution. and maybe not. but it's worth a try, IMHO.