209z28

Hello everyone.

New to the forum... not so new to Camaros haha. I have a 97 z28 159k mi and still runs strong. Have replaced alot on the car and from what i can tell the car is sound in neqrly every department. However... yesterday i replaced my trans mount in an effort to reduce shifter hop while on the freeway (replacing this did fix the hop) however, when I am leaving a light under heavy or moderate throttle or am above 2500rpm and apply quick snappy throttle, i get a bellowing thump or popping sound under the floor. It is coming more from the passenger side near the center of the car and slightly forward of the shifter... my best guess is putting in a new mount made the rear of the trans move up and i still have old motor mounts and is causing the trans to hit the tunnel or possibly the factory exhaust to hit the floor? Also, i must note, this popping only happens on DECEL. And finally, i did replace the FPR for other reasons but the sound occurred before i replaced it, isolating my sound to the trans mount issue. Car does not run rich, is good on gas, and exhaust does produce a gurgling sound but is fine due to straight pipes after cats... i will be getting back under it to check it out, just curious if anyone has had this happen AFTER replacing a new mount. Again engine mounts are suspect, but i fear replacing them will move the engine further upward and if something is hitting the floor i dont that will help. Last best guess is passenger motor mount may be as hard as a cup of pudding and everytime i come off the gas the mount may be slamming back into the opposing mount... or maybe i need to retighten the trans support bracket? Lol. Like i said just looking for insight, but i will be back under the car soon. Thanks everyone.

fex77k

iTrader: (2)

Is your torque arm mount shot or loose?

209z28

The torque arm mount has seen better days but its not completely shot... I was pondering everything I did yesterday and I recall I did all of the work from the drivers side and i will confess to not completely checking the bolts on the trans cross member on the passenger side. I believer they were snugged but i dont 100% recall torquing them down... this could explain it... when theres positive torque, trans lifts up, let off gas, trans falls back onto bolts holding up mount. If it is as simple as tightening 2 bolts that would be awesome. I guess im just "bench fixing" for now until i get underneath it... haha.

fex77k

iTrader: (2)

yea gotta be a loose bolt.

209z28

It was... the two bolts on the passenger side of the crossmember were about2 full turns out... tightened em up... all is good...

fex77k

iTrader: (2)

Thats better than what I did to my M6 94Z, I went over a water turnoff cover and ripped the crossmember off the car, had to weld the mounts back to the unibody.