I have a clunk or thud that seems to happen somewhere in front of my feet. It only seems to happen when the car jerks, ae hard launches Might this be the motor mount? if so how hard/expensive is it to fix?

 

Might be a trans mount, common.

 

More info about your car would be helpful. But we'll just assume you have a stock 99 Z28. You probably have ar 50,000 miles on it. In that case I'd suspect that the transmission mount is probably toast. If you're handy with a wrench it'll take about 30 minutes to replace with a couple wrenches, a set of ramps and a hydraulic jack. New tranny mounts range from around $20 to $35. On a scale of 1 to 5, 5 being the hardest. I rank this one a 1. Right there with changing your oil. All you do is support the tranny with the jack. Remove all four bolts holding the crossmember in place. Remove the nut holding the crossmember to the mount. Remove the 2 bolts holding the mount to the tranny. Install in the reverse order. You might have to do some pushing and shoving on the tranny to get the crossmember to line back up properly on the unibody. Be sure to leave the nut that holds the mount to the crossmember loose until everything else is tight. That's it.

A poly bushing will be stiffer and will probably outlast a new rubber one. But they also transmit more vibration through the car and some people regret putting one in.

Good luck.

 

Sorry ... I changed my sig just after I posted this. I went thru a tranny mount or 4 on my Lt1 as well The gearbox also seems to whine in every gear but 4th....but im sure thats another problem alltogether.

 

I had my car checked out yesterday and it turns out it IS in fact my motor mount ... rear right. Any thoughts on price? Is it a tough job to do myself?