deep, grinding sound when shifting into gear and out of gear

[jerseyjon]

1985 5-speed cabriolet.- I am getting this horrendous sound from my car when I first turn it on and when I am riding in a lower gear going slowly or when I am driving faster and ease off the gas. I thought at first it was the gears misaligned or loose because it was only doing this in first and second gear. my shop replaced the seals, gaskets and bushings as there was a pretty bad leak- someone had used the wrong seals/gaskets earlier in this poor cars life. the sound it is making is just aweful - like a deep resonating, almost grinding sound..very loud and vibrates the dash pretty good. it only does this at lower rpms and when at speed while giving it gas it is quiet. the engine was steam cleaned at the shop as well to check for any other leaks - maybe the motor mounts are bad and now that the gunk is gone have loosened up quite a bit? Also , I would have assumed that the shop would have checked the fluid levels in the trans when they replaced all the seals, but maybe they didnt and it is low?

[Briano1234]

It could either be the Wheel bearings or the Self Machining Syndrome which will destroy the Transmission.

[jerseyjon]

just drove back from work and i'm thinking it may be an exhaust problem maybe - I'll have to get under the car tomorrow and take a look. it is making the noise at idle as well as while in gear driving without giving it gas - as soon as I accelerate it goes away. it's a low pitched box of marbles kind of sound as well.

[gull]

If you only hear it when you're coasting in gear, it may be a bad engine mount or trans mount. Mine went bad once, and when I coasted in gear the engine would move and cause the exhaust to hit part of the underbody, making a horrendous buzzing/rattling noise.