How to Quiet Noisy Manual Transmissions

It is not uncommon for a manual transmission to create noise, but it is making an excessive amount of noise there may be a problem. There are a few things you can do to try to make the transmission sound quieter.

• Try to determine at what point the transmission is making the noise, such as is it making the noise while you are shifting the gears or while you are driving. The noise could be the gear oil level being low, worn bearings or gears or the bolts on the bell housing being loose. Bring all the fluids to their recommended levels, tighten any loose belts and replace any worn or loose gears. Doing these things should correct the problem.


• If the noise is happening while you are decelerating it could be due to the engine mounts being loose, a worn differential pinion shaft or worn joints. Replacing the worn joints and pinion shafts and tightening the engine mounts should more than likely solve the noise problem.


• If you hear a gear rattling noise while you are driving it could be due to worn bearings, old gear oil or worn out gears. Replace the gear oil and bring it to the recommended level and replace the worn gears and bearings and it should take care of the noise problem.


• A broken synchronizer, worn gears or a defective clutch would result in a gear clash noise when shifting. Replacing the broken synchronizer, forward gears or replacing the defective clutch would more than likely solve the noise problem.