Hi all,
I have a irocz 1986 with a crate 350 engine with about 100 miles on it and recently rebuilt T5 manual transmission. When I am on low gear and speed about 10 mph, there is clunking sound, like metal to metal, right below the transmission area. It almost feels like the whole transmission and driveshaft are loose and hitting just about anything underneath. I was thinking the transmission mount was loose. I have not It take look at it yet as I would like to know how and where to start. Any suggestion is appreciated.
Thanks.

 

transmission mount. Put it in gear and try to move forward with the Ebrake on. If you look at the engine and it looks like its gonna roll outta the engine bay(tipping forward, tailshaft raising up against tunnel), you have a bad mount. Check engine mounts too.

 

Yeah, that's what I thought. can the transmission mount seen from underneath the car as well?

 

Yes, right at the trans crossmember

 

When you remove the crossmember, hit the bolts with some PB blaster, and don't be too rough on 'em. The threaded crappy inserts in the frame can strip pretty easy.

 

Great advice! Thanks

 

Usually just looking at the rubber mount from underneath is not enough because the rubber tears away from the steel its mounted to not in half.

When there is pressure on it from the transmission it looks OK. You must place a jack under the trans pan with a large enough piece of wood on it so the jack will not punch through or bend the pan and jack it up a tiny bit and watch the mount. If you see it separate than replace it.

This is a VERY common problem and after tearing a few I went to a "poly mount" instead of rubber.
They are basically made for racing applications.

 

Thanks for the advice! I am planning to do check it tomorrow.

 

Probably the mount. Check out the torque arm bushing while you're under there. If the bushing wears out the torque arm can knock against the clamshell mount and make a clunking noise.

 

I second jacking up the back of the tran to check it, when they break the crack/separation is almost invisible unless pressure is applied to it, since you have a 5 speed you should be able to change it just by jacking the back of the trans up, you shouldn't need to remove the crossmember, also look into a poly mount, the ones from energy suspension have interlocking tabs inside of them to keep them from seperating

 

The transmission mounts were fine. Like shayne said, the torque arm bushing was not there. Apparently the previous owner tried to weld everything together.

I thought a follow up would be good.

 

Energy Suspension makes solid poly replacement bushings, just drill out the rivets on the clamshell mount (if the PO didn't already). Make sure to get the correct bushing for your mount, the "lips" on the torque arm can face either the driver side or passenger, resulting in a W or M shape, depending on how it's oriented.

 

I will check them out! Thanks.