hey guys, I just bought a 2000 C5 with the 6 speed, there seems to be a howl either in the tranny or the rear end but it hasn't gotten any worse since I've been driving it....any ideas as to trouble shoot or has anyone had similar problems....any ideas would be appriciated

 

I'm guessing it's the differential gears. Had the previous owner swapped them out for any reason?

 

Dave...I don't think anyone has changed the diff., with the tranny and the rearend being so close it's hard to tell, I would think driving it would make it worse but hasn't....probably put 5000 miles on it....my sweetheart drives it to work 4 days a week around 200 miles round trip and nothing has gotten louder....what do you think????

 

It still could be that the car wasn't broken in correctly. The manual and movie (that came with each C5) warns new owners to not exceed 55 MPH for the first 500 miles. This is not because the engine needs to be broken in; rather, it prevents geartrain noise from occuring down the road (so to speak). You try changing your tranny and differential fluid. I just changed mine with Amsoil Universal synthetic ATF (for manual tranny C5s) and their SVG 75W-90 gear lubricant for the diff. If you use this SVG gear lube, you do not have to add the friction modifier, since it is built-into the SVG lube.

Some owners have experienced less noise after doing these fluid changes.

Dave