I have been having strange rattles coming from under my car lately. I think i may have a broken trans mount. when I accelerate lightly I hear something moving under the car. at first i thought it was my headers but it sounds like something is just freely bounceing around under my car. it seems to be coming from under the passenger floor in front of the seat. Is that where the trans mount is? I did drive my car on mt et street radials so i'm sure my driveline took a bit of a beating this summer. what do you think, is it broken?

 

A heavy thumping under acceleration if it's totally
let go.

I'd be more suspicious of Y-pipe clearance and
the motor mounts maybe being a bit soft.

 

if you want to check your mount just support the tranny and pull the four bolts out of the cross member. If the mount is bad the crossmember is going to fall on the ground or it is going to be really floppy. I'd be more suspicious of my heat sheilds and my flexplate

 

Or just throw a board on a jack and place it under your tranny pan. If the tranny lifts off at all it's shot...

Even if it's not shot, if you've been going hard on it for a while, a new energy suspension mount is only like $23...