Manual Transmission Noise during acceleration in only 1st and 2nd

[dbeaulieu]

I have a 1985 LX with the 5.0 and a manual transmission. When I accelerate more than any bit as powerfully as a Limo driver I get a clacking noise and feeling coming from the somewhere below my feet. If I drive the car for like 40 minutes the noise seems to go away. Also if I shift extremely gingerly the noise won't happen. Basically the faster I let up the clutch peddle the louder the noise is. The noise only happens during acceleration, not decel or coasting and not in 3rd fourth or fifth. This seems like a flywheel/clutch/alignment issue but I don't know. I'm hoping someone here has had this or can at least point me in the direction of knowing what to look for.

This is the last thing on the car that I really need to fix apart from the suspension!

 

[broncojunkie]

The last time I had a similar issue, it turned out to be the exhaust flange hitting, iirc, the transmission crossmember. All I had to do was loosen the flange bolts a bit and tap the flange around with a hammer, then re-tighten. Having said that, if you're having a similar issue, I would be looking at other things that could result in movement or repositioning of the drive train. Common problems are motor mounts, transmission crossmember mounting bolt bushings, and transmission mount itself. All of those parts are prone to wearing out and causing issues. I would rule those out before digging into the bellhousing/clutch/flywheel stuff.

 

[dbeaulieu]

The last time I had a similar issue, it turned out to be the exhaust flange hitting, iirc, the transmission crossmember. All I had to do was loosen the flange bolts a bit and tap the flange around with a hammer, then re-tighten. Having said that, if you're having a similar issue, I would be looking at other things that could result in movement or repositioning of the drive train. Common problems are motor mounts, transmission crossmember mounting bolt bushings, and transmission mount itself. All of those parts are prone to wearing out and causing issues. I would rule those out before digging into the bellhousing/clutch/flywheel stuff.

The exhaust was just redone before I got it so hopefully it’s something with that. However there is a strange oscillation when I accel as well though so wouldn’t be a surprise if it’s a combination of stuff. I’ll check all the stuff you said. Thank a bunch for the input.