C3 Transmission jerky
Thread Starter
Intermediate
Joined: Aug 2008
Posts: 42
Likes: 0
From: Delta Ohio
C3 Transmission jerky
Hi All
I have a 1980 C3. the transmission and engine are stock and I had the tranny rebuilt 2 years ago due to it being kinda jerky, 82k on it. it was shifting between 2nd and 3rd at low speeds around 20-30mph. well after the rebuild it still does the same. the shop that did it is of no help to me. I was overseas when my wife had it done and it was 6 months later when I got home. I live in rural northern Maine and not much help up there. I am an aircraft mechanic so I am pretty mechanical but transmissions are not my thing. does anyone have any help that can point me in the right direction to help fix the issue? it is really annoying.
thanks
Larry
I have a 1980 C3. the transmission and engine are stock and I had the tranny rebuilt 2 years ago due to it being kinda jerky, 82k on it. it was shifting between 2nd and 3rd at low speeds around 20-30mph. well after the rebuild it still does the same. the shop that did it is of no help to me. I was overseas when my wife had it done and it was 6 months later when I got home. I live in rural northern Maine and not much help up there. I am an aircraft mechanic so I am pretty mechanical but transmissions are not my thing. does anyone have any help that can point me in the right direction to help fix the issue? it is really annoying.
thanks
Larry
Race Director
Joined: May 2006
Posts: 18,692
Likes: 2,572
if you have a cable operated shift on the throttle it may not be correctly adjusted. I believe the procedure is to release the lock lever at the throttle bracket fully open the throttle and relock the cable lever.
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
You also have a vacuum modulator on the tail shaft. Vacuum from the engine tells the trans to up shift. Check the vacuum line going to it . If the line is good, there is also a tiny flat head screw in the vacuum port. Pull the line and turn the screw and your shift points will change.
The jerking feeling may also be coming from the lock up converter TCC. I'm pretty sure 1980 corvettes have them but don't quote me.
The jerking feeling may also be coming from the lock up converter TCC. I'm pretty sure 1980 corvettes have them but don't quote me.
