When ever in reverse I can hear a low tone moan or groan, not really a whine, sounds kinda like a front wheel drive vehicle when they back up kinda quick, but more low toned. It doesnt make any other sounds really other than in reverse, The gear oil has been changed twice with in a 3k mile span, and I have some GM limited slip additve in it as well, and the level is not low. Is this concidered normal? Thanks

 

Anyone have any ideas.

 

Mine sounds normal and quiet. But it would make that sound if I'm backing up at 20 MPH. Are you sure it is the rear? Harmonics can be strange... especially if the trans fluid is low. Have a buddy outside and listen while you back up. Better yet, have the buddy back the car up and you outside listening. Keep us posted.

 

From inside the car it seems like it's comming from the rear, the tranny was rebuilt like 2k miles ago, and it's not low on fluid either. I guess it could be from the tranny, definitly from the driveline though. Thats a good idea about listening from outside, specialy sense it's only a low speed thing. I'll check it out this weekend and post back. Thanks

 

You'd be surprised what you can here when your standing outside your own car... you'll notice every squeak, rattle, that you've never hear before. I'd just make sure the fluids are topped off before testing. Good luck.