Question: rear end noise

[sett2vett]

I hear a grinding sound in the rear end, but only when I'm in reverse backing down my driveway and only on the first time of the day. There is no grinding heard during any subsequent back-ups. There is no grinding sound when driving forward. I have a 2006 coupe with 9200 miles on it and treat it like a baby.

Any ideas?

Thanks.

 

[Tuna]

Time to have the diff serviced with new updated fluid.

 

[Hib Halverson]

Changing fluid will only address limited slip noise or chatter.

If the noise occurs when the car is moving in reverse but going straight, it's unlikely the noise is from the limited slip. On the other hand, if it happens when you are backing as well as turning, it could be the limited slip but it might be something else.

Typically, if the limited slip makes noise or chatters, it happens in turns but doesn't change with direction forwards or backwards.

 

[sett2vett]

Thanks, guys!! It only grinds in reverse and while turning at the same time --- great point!!! I'll have it serviced asap.

 

[Hib Halverson]

Take "Tuna's" advice and have the rear axle lube changed.

 

[sett2vett]

Had the diff. serviced with Amsoil Severe Gear 75W90 and limited slip additive------no more grinding!!!!!!!!!

Thanks.

 

[Tuna]

Great news.

Our '06 has 60K miles and has had the diff fluid serviced 3 times now. Our '08 with 37K miles - none. Must be some thing about the '06 diff but it likes being serviced a little more often.

 

[NORTY]

Great news.

Our '06 has 60K miles and has had the diff fluid serviced 3 times now. Our '08 with 37K miles - none. Must be some thing about the '06 diff but it likes being serviced a little more often.

Actually, during GM's "learning curve" on this, they tried to first replace just the fluid to no avail. Then, they tried new fluid with add'l friction modifier. That didn't work very well either. Then, they added 2 bottles of friction modifier to rear ends w/chatter. That worked! Then, GM had their gear oil supplier add the 2 bottles of modifier to their new GM lubricant part #. Now, all you need is to go to your smiling Chevy dealership and tell them you are in for the "Grinding/chattering rear end while cold and turning" recall, and they fix you up fer nuthin'!