Rear end noise

I have a 1998 Firebird Formula LT1. For the past year my Posi rearend makes a rubbing sound that is very annoying. Car runs perfect. Anyone have any ideas what is wrong with the rearend that could cause a continuos rubbing sound? Of course at high speen noise is negligible but in traffic noise is a lound rubbing noise. Any help would be highly appreciated.
Thanks
Vic Liotta

First I would check to see if something is making contact with the drive shaft.
Next i would check for a bad u-joint.
If the noise happens all the time, may be a bearing..if it makes more noise on accel than decell or vice versa it could be the gearset.

First , there is no such thing as a 98 Firebird LT1 unless you had it put in custom. Otherwise you have either a LS1 or a 3.8 and are you sure its not from a sticking emergency brake cable/caliper or it could just be old rear end fluid were the posi additive broke down or a bad differential bearing or any of the things merlin mentioned.

BTW- Welcome back Merlin.

First , there is no such thing as a 98 Firebird LT1 unless you had it put in custom. Otherwise you have either a LS1 or a 3.8 and are you sure its not from a sticking emergency brake cable/caliper or it could just be old rear end fluid were the posi additive broke down or a bad differential bearing or any of the things merlin mentioned.

BTW- Welcome back Merlin.
Hi,
Guess I was wrong about the LTI..I thought the detuned 350/305hp was the corvette aluminum engine. I had it to a mechanic and he wasnt sure what it was. Can the rear end posi gear box be replaced?
Thanks for your response
Vic