Rear End

[silverado19]

My 2001 Chevy Tahoe 2wd has the limited slip rear end, code G80. I recently serviced the rear end as described on this site.

 

I did not put in the addative from GM for about the first 100 miles or so. The addative is in the rear end now. I noticed the code if the glove box after about 100 miles.

 

I am currently hearing some noise from the rear end. It sounds like it is coming from the u joint that links the rear end to the drive shaft. The noise sounds bad sometimes like it is one of the rear breaks and seems to get worse when I apply the breaks. Other times, I can hear nothing and the reard end sounds great, no noise.

 

I jacked up the rear end, turned the wheels by hand and seems like I confirmed the noise is coming from the rear end u joint....as best I can tell.

 

My question is this....did I damage the rear end by not putting the addative in right away? I used Red Line Oil 75w90. I never heard this noise before. Could it be a coincidence the noise started when I serviced the rear end? Could this noise be soemthing else?

 

I am taking it in this week and was looking for some advise.

 

Thanks

[Smither]

I was getting conflicting information, so I sent an email to Eaton about the G80 locker rear end. My reply back stated that NO additive is required in the G80 locker. So, you did not hurt anything by not putting additive in. I don't know if you hurt anything by putting it in.

[Butch 02 Denali]

No additive is needed because the recomended synthetic oil already has the additive in it. All synthetics are rated for limited slip/posi use, so unless your getting popping/clicking noises on corners, no more additive is needed. I've had some that needed 2 bottles. No you didn't hurt anything! Could it be your slip yoke sticking in the back of the tranny? That's a common noise/problem in these trucks.

 

Butch 02 Sierra Denali

[frdfandc]

I've been told by a former GM mechanic (fellow Honda tech now) that the additive can cause noises from the rear diff if the vehicle is equipped with the G80 and to just put the synthetic fluid in of proper weight.