Lowered Whine

[Modded]

Hey guys, I recently had my Tahoe in for a issue that I thought was a TSB. I am getting a whine from the rear area, I think it is the differential. THe interesting part is that when I installed the Pedders rear coils I pulled the rubber isolators to get a better drop under my belt. Now I hear a noticable whine coming from the rear when I am cruising with the foot off the gas at low speeds (under 20MPH).
The dealership said it MAY be related to the rubber isolators not being in there and offered to reinstall for $90, but I want to check and even see if thats the cause.
Keep in mind if it is I could reinstall those isolators by myself in like 30 minutes.

Can you'll help me, especially those who have lowered, no matter the year!

 

[mdtahoe]

I really do not think the isolators could be causing you problem. Your description is exactly what a bad pinion bearing would do (internal in the diff). Unfortunately you probably will need to install the isolators to get the dealer to warranty the rear end repair, which should be covered under the 100,000 mile powertrain warranty.

 

[Modded]

Thanks man, I forgot to update earlier but he reinstalled the isolators for free and it still whine, so he then put it in for a new ring and pinion to replace the bad one!
Do you know what exactly cause stuff like a bad pinion?