I just installed a used transmission out of a wrecked car in my cobalt. The transmission had about 32k miles on it. Everything seems fine except every once in a while it pops out of third and fifth gears when I let out of the throttle. This seems to be more apparent when it is cold. My first thought were the syncros, but this seems a little too early for syncro issues. Also its on third and fifth gears. It does almost feel like the cables are out of adjustment and I am reaching all the way to the top of the throw to get it into gear. I did put Valvoline Dex 6 transmission fluid as recommended by the local auto parts store's database. I do have the Hurst Short throw, would I pull the center console apart by the shifter and adjust the adjustment on the drivers side cable to resolve this issue? I made sure the shifter cables on the transmission side are in the bracket on the transmission and it is secure on the transmission. Any help on this will be greatly appreciated.

Thanks!

 

first off, dexron VI is the wrong oil for the ss/sc. there is some mis-information out there on the fluid type, even alldata says its dexron III or dexron VI. the truth is, it requires a specific gm fluid only avalible from gm or saturn. dexron fluids are completly wrong for it and if you keep running it, you will cause damage. change it ASAP

you dont have a syncro issue, syncros are only used to match the rpm of the gear while shifting into that gear. once the shift is complete the syncro is just along for the ride. it sounds like your shifter cables are out of adjustment and its not completly going into 3rd and 5th. if the shift sleeve is only part way over the teeth on the gear its easy for it to pop back out. re-adjust the shifter cable and im sure it will be just fine.

 

Specifically how would I go about adjusting the shifter cable?

Alright, I will locate two quarts of GM part No. 21018899 Tomorrow.

 

Any other advice?