i have a 3.1 automatic firebird with a 700R4 automatic transmission. There is a loud knock from the transmission when shifting from 1st to 2nd gear. It doesnt feel like its slipping too bad but it is a very loud knock and you can definitly feel it. If anyone could help me figure out what it could be that would be great. Thanks!

 

I have a 92 Firebird 3.1 with a 700R4 auto transmission. When the car shifts from 1st to 2nd gear it has a loud knock and the car shifts very hard. It only does this when at a higher RPM. It doesnt do it if you leave easy. It does it aroune 3500-4000+ RPM. If you can help diagnose this that would be great. Thanks!

 

Check the 2nd accumulator spring, common for them to break.

RBob.

 

Ok i will. Do you think it could also be the bands? Or maybe needs an adjustment of the TV cables?

 

Only one band, it may be it, don't know until you check. The TV adjustment is easy to check, open hood, rotate throttle fully open, check that the cable is tight, done.

While under there also check the transmission mount, they tend to break and can allow the rear of the trans to flip upward and bang.

If nothing else has been done to the trans a larger boost valve is a nice upgrade.

RBob.

 

RBob beat me to it. Mine broke a trans mount after I put a shift kit in it.

 

Ok thanks!