noise from rear end

[Camaro Dom]

hey, i got this kinda odd problem here and i'd like a little input as to what it might be:

basically, i hear a grinding noise (actually it sounds kinda like something is spinning against something that isnt spinning) when i drive over bumps in the road. like i'll hit the bump, and it'll grind for a second or two and then stop. usually only happens in slippery conditions like dusty snow or rain. it sounds like its coming from the left rear wheel but its hard to tell. i've changed tires and i'm almost positive its not the wheel rubbing on the fender. sounds like metal. very loud noise, and it happens when i'm braking, coasting or accelerating. its got 90k on it and as far as i know the diff fluids never been changed. could that be it? i feel a slight drag when it happens too. thanks in advance!

[hockeyman]

The FIRST thing I'd check (if I were you) is the fluid level in the differential. That is the most important of all! If it hasn't ever been changed, then I'd make an appointment with a mechanic or do it yourself asap.

It sounds like a bad U-Joint though. When they go bad, they make a horrible grinding noise when the car is moving in any direction and at any speed.

[Camaro Dom]

if i'm gonna replace the u-joints, should i just replace the whole driveshaft? i knwo that my rear oil seal on the trans is a little leaky so i'm probably gonna hafta do that anyways. speakin of which, how hard is it to replace that seal?

[ezrollin]

get an aluminum driveshaft, it would be a slight upgrade over stock.
very easy to do
just unbolt 4x small bolts, like 9mm
pull it out, easy

[Minor723]

I had a grinding noise once, and it ended up being a failing bearing that i ignored and ended up having to have my whole rear end replaced... Get your fluids checked back there for metal shaving asap.