Jumpy T10.......
Thread Starter
Heel & Toe
Joined: Mar 2007
Posts: 23
Likes: 0
From: Michigan
Jumpy T10.......
I’m having problems with my T10 jumping out of 2nd gear during deceleration when driving in 2nd for awhile (such as cruising through a neighborhood). It does not jump out during acceleration.
I have talked to a few C1 owners in my area who say that they have the same problem.
Any ideas?
I have talked to a few C1 owners in my area who say that they have the same problem.
Any ideas?
Melting Slicks
Joined: Jul 2000
Posts: 2,097
Likes: 99
From: Boston MA
Very common problem in the day. Although I remember it was usually 3rd gear. Only happens on de-acceleration.
Sorry for the bad news, but the transmission needs to be rebuilt. Believe it's the synchros. Look around for an expert. Even better, look around for an expert who will guaranty his work. Also very common for the problem to continue after the rebuild. The fix is one that requires new parts and a fussy adjustment by somebody who knows what they're doing. Throwing the transmission together without care only means the problem continues even though lots of internal parts get replaced.
Sorry for the bad news, but the transmission needs to be rebuilt. Believe it's the synchros. Look around for an expert. Even better, look around for an expert who will guaranty his work. Also very common for the problem to continue after the rebuild. The fix is one that requires new parts and a fussy adjustment by somebody who knows what they're doing. Throwing the transmission together without care only means the problem continues even though lots of internal parts get replaced.
Safety Car
Joined: Nov 2004
Posts: 4,182
Likes: 94
From: going faster miles an hour...with the radio on in browns mills new jersey
Out of curiosity, does it do it at any specific rpm?
I used to have an '84 with the 4+3 transmission. It would pop out of 2nd on deceleration at either 1700 rpm or 2700 rpm and nowhere else.
I never did find out what the problem was. Chevy's "fix" was to replace the transmission. While waiting to have my problem resolved, I lived with it by avoiding the combination that would cause it to pop out of gear.
Good luck with your transmission.
I used to have an '84 with the 4+3 transmission. It would pop out of 2nd on deceleration at either 1700 rpm or 2700 rpm and nowhere else.
I never did find out what the problem was. Chevy's "fix" was to replace the transmission. While waiting to have my problem resolved, I lived with it by avoiding the combination that would cause it to pop out of gear.
Good luck with your transmission.
Thread Starter
Heel & Toe
Joined: Mar 2007
Posts: 23
Likes: 0
From: Michigan
I have not seen this condition at a specific rpm.
I had the trans rebuilt by an expert who only does T10 transmissions and has been doing so for over 30 years. He told me before he started that this was a common problem and could not guarantee that it would not continue. I had a number of worn parts replaced to no avail.
I had the trans rebuilt by an expert who only does T10 transmissions and has been doing so for over 30 years. He told me before he started that this was a common problem and could not guarantee that it would not continue. I had a number of worn parts replaced to no avail.
Burning Brakes
Joined: Jan 2007
Posts: 970
Likes: 5
From: Hagerstown MD
First, make sure the shifter is correctly adjusted. The internal parts that typically affect the inability of the transmission to remain in gear upon deceleration are the front "dogs" or teeth on the gear that mesh with the clutch hub or slider and the slider itself. The brass synchros or blocking rings usually will not cause that malfunction. Close inspection of the small teeth on the front of the gear and the corresponding grooves inside the clutch hub aill show they have a taper that helps hold the hub and gear in contact under load. The small teeth will become worn and the taper will flatten out allowing the hub to "pop" out of gear during high load conditions.
Race Director
Joined: Mar 2001
Posts: 14,632
Likes: 4,683
From: Mustang OK
2026 Corvette of the Year Finalist - Modified
2025 c1 of the Year - Modified Winner
2024 C1 of the Year Finalist - Modified
2023 C1 of the Year Finalist - Modified
2015 C1 of the Year Finalist
If all is properly adjusted, and the tranny is in otherwise good condition and the pilot bushing in the rear of the crank is not enlarged, then no matter what, a complete teardown/rebuild will be the only answer. BUUUUUUUUUUUUUUUUT, instead of replacing 2nd gear, just install Tork Loc synchro sliders------------------------------there is a 99% probability this will permanently cure the jumping out of 2nd gear. If you cannot, or do not, do your own tranny rebuilds, any qualified, experienced 4sp builder will know EXACTLY what Tork Lock sliders are. Almost without exception, for 4sp trannys that have considerable wear and lots of mileage, I always replace the stock sliders with Tork Loc sliders.
Here is a comparrison of a Tork Loc (left) and a stock slider. Notice the additional back cuts on both sides of the splines in the Tork Loc slider. These back cuts help to "pull" the slider deeper into the engagement teeth of the selected gear.
Here is a comparrison of a Tork Loc (left) and a stock slider. Notice the additional back cuts on both sides of the splines in the Tork Loc slider. These back cuts help to "pull" the slider deeper into the engagement teeth of the selected gear.
Last edited by DZAUTO; Dec 3, 2007 at 08:22 PM.
Race Director
Joined: Mar 2001
Posts: 14,632
Likes: 4,683
From: Mustang OK
2026 Corvette of the Year Finalist - Modified
2025 c1 of the Year - Modified Winner
2024 C1 of the Year Finalist - Modified
2023 C1 of the Year Finalist - Modified
2015 C1 of the Year Finalist
By the way, I REALLY, REALLY, REALLY wish you people would quit using the term C1, C2, C3, etc, etc. From year model to year model, there are frequently changes that may seem insignificant, but often these changes can be VERY important. These early B-W 4spds are a perfect example!!!!!!!!!!!!!
IF the above 4sp issue is a 57-60, there is a VERY IMPORTANT (but simple) modification that needs to be done when installing Tork Loc sliders.
IF the above 4sp issue is a 57-60, there is a VERY IMPORTANT (but simple) modification that needs to be done when installing Tork Loc sliders.
Last edited by DZAUTO; Dec 3, 2007 at 08:32 PM.
