4spd shifter problems
Thread Starter
Instructor
Joined: Jan 2012
Posts: 214
Likes: 6
From: Mebane, NC
4spd shifter problems
Happened twice last week, somehow shifting from second into third, the first gear lever is moved out of the neutral position enough to lock the tranny in third gear. Will the rebuild kit offered by Zip and others fix this problem?
Pro
Joined: Aug 2010
Posts: 698
Likes: 8
From: Stockholm Sweden
It sounds like you have to adjust your shift linkage.
On the Vettes the gearbox and engine have rubber mounts while the shifter itself is mounted solid in the gearbox crossmember.
As the engine and gearbox mounts sags due to age your linkage may need some adjustment to be perfect.
If you have a HURST shifter in your car the shifter is mounted directly in the gearbox and is not depending on the engine mounts.
It is critical for health of the gearbox that the linkage is correctly adjusted.
On the Vettes the gearbox and engine have rubber mounts while the shifter itself is mounted solid in the gearbox crossmember.
As the engine and gearbox mounts sags due to age your linkage may need some adjustment to be perfect.
If you have a HURST shifter in your car the shifter is mounted directly in the gearbox and is not depending on the engine mounts.
It is critical for health of the gearbox that the linkage is correctly adjusted.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
If that is OK....then I would be feeling for the detents when I am under the car...manually moving the linkage. You could have issues internally in the transmission where the fingers that go into your sliders ....or a possible broken spring.or worn detent.
Worn out linkage also...hard to say.
DUB
Thread Starter
Instructor
Joined: Jan 2012
Posts: 214
Likes: 6
From: Mebane, NC
more info
Thanks for the suggestions. Some more info. The trans was rebuilt winter before last, new shift arms, detent springs, etc. Don't think it is internal. Standard shifter, linkage was adjusted with shifter in neutral and trans arms in neutral, think linkage adjustment is ok, but if there is a better way to do it please tell me. Engine/trans mounts are recently changed. Haven't been under the car in that area in a while, will look tomorrow.
DUB, would the rebuild kit accomplish the same thing as compressing the housing? I don't have a good feeling about bending metal that is 40 years old.
DUB, would the rebuild kit accomplish the same thing as compressing the housing? I don't have a good feeling about bending metal that is 40 years old.
Melting Slicks
Joined: Apr 2006
Posts: 2,084
Likes: 14
From: Airdrie Alberta
I rebuilt mine a while back and it tightened it right up.
They take a lot of abuse with 40 year old grease full of dirt ,grit & rust.
There was a fair amount of wear on the pins, and shims so after complete dissassembly I cleaned, and reassembled with new parts. once installe i adjusted it using the maintenance procedure
https://www.corvetteforum.com/forums...uncie-m21.html
was like a new car after
They take a lot of abuse with 40 year old grease full of dirt ,grit & rust.
There was a fair amount of wear on the pins, and shims so after complete dissassembly I cleaned, and reassembled with new parts. once installe i adjusted it using the maintenance procedure
https://www.corvetteforum.com/forums...uncie-m21.html
was like a new car after
