grinding noise in reverse whille in gear not shifting into it

[Mikej]

When my car is in reverse it will make a loud rubbing noise, its not really grinding like its not in gear but a loud rubbing that sounds like i'm hitting something when it goes in reverse. Seems to do it louder when the car hasnt been driven for a couple days. Almost like its got something to do with the drive shaft like, once per spin it will "rub" slower i go the longer it will take to make the noise, and the quicker i back up the faster together the noise is. anyone have a similar problem? 94 fwd gst.

 

[viprez586]

Have you looked at your driveshaft?
Serviced the transmission, front T-case, Rear diff? (fluids)

I'd start there since its good maintenance.
Worst case is since reverse is not synchronized either your reverse idler or reverse gear have some chipped/worn teeth.