c4 auto transmission shifting
Thread Starter
Heel & Toe
Joined: Apr 2013
Posts: 19
Likes: 0
c4 auto transmission shifting
I have seen some threads on here a while back about this problem, but need some help with my auto tranny. In talking to some Vette owners in my area of central Florida, they have told me to stay away from the dealers. Most techs now a days weren't even in diapers when the '85 was in production. So I guess I will have to tackle this myself. The shifting points in my C4 are all off. It wants to run through all the gears before I hit 40MPH. I know this is not right, though this is my first Vette.
If somoeone could give me some advice on how to adjust or what ever it is I need to do to protect the tranny from any damage I would approceiate it. The engine has 80K miles and runs great. I added some SeaFoam to the tranny to see if it might just need some cleaning but it dos not seem to help.
If somoeone could give me some advice on how to adjust or what ever it is I need to do to protect the tranny from any damage I would approceiate it. The engine has 80K miles and runs great. I added some SeaFoam to the tranny to see if it might just need some cleaning but it dos not seem to help.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
That sounds like normal operation to me. The engineers set up the shift points to be as low as possible to increase gas mileage.
My car will shift into second just by letting it idle in first gear. Then it lugs and drops back into first.
My car will shift into 3rd at very low speed, like 12 MPH if I give it very light throttle.
I don't drive in OD unless I'm going over 50 MPH, so I don't know what speed it will shift at.
On my car TCC is programmed to lock up at 40 MPH. It doesn't matter what gear it's in.
My car will shift into second just by letting it idle in first gear. Then it lugs and drops back into first.
My car will shift into 3rd at very low speed, like 12 MPH if I give it very light throttle.
I don't drive in OD unless I'm going over 50 MPH, so I don't know what speed it will shift at.
On my car TCC is programmed to lock up at 40 MPH. It doesn't matter what gear it's in.
Drifting
Joined: Feb 2008
Posts: 1,537
Likes: 178
From: NE Ohio
2024 C4 of the Year Finalist - Unmodified
Yep. 37mph to 4th or OD
That sounds like normal operation to me. The engineers set up the shift points to be as low as possible to increase gas mileage.
My car will shift into second just by letting it idle in first gear. Then it lugs and drops back into first.
My car will shift into 3rd at very low speed, like 12 MPH if I give it very light throttle.
I don't drive in OD unless I'm going over 50 MPH, so I don't know what speed it will shift at.
On my car TCC is programmed to lock up at 40 MPH. It doesn't matter what gear it's in.
My car will shift into second just by letting it idle in first gear. Then it lugs and drops back into first.
My car will shift into 3rd at very low speed, like 12 MPH if I give it very light throttle.
I don't drive in OD unless I'm going over 50 MPH, so I don't know what speed it will shift at.
On my car TCC is programmed to lock up at 40 MPH. It doesn't matter what gear it's in.
Drifting
Joined: Aug 2010
Posts: 1,704
Likes: 8
May be your governor isn't a Vette governor.You can fine tune your shifting point by changing governor weights and springs.You can use a shift kit to make your shifting firmer and agressive.Change TV cable setting let you raise shifting point,but most trans rebuilder dissuade you from doing this.
