Had an Eaton LSD with a set of OEM 3.42's put in the 10-bolt of my truck in early July. I purchased all the parts from Ron's and took it to a shop about 20 miles from my house. The gentleman installed the gears and LSD in the truck and set the backlash to .003''.

I put a T/A cover on using RTV and torqued the bolts (including the preload) correctly. The cover leaked and the noise started when the fluid was low I'm assuming. I replaced the RTV with a GM gasket and it hasn't leaked since.

Now the rear is making a wailing noise but, only when I turn corners (either direction) and only when the rear is up to operating temp...not when it is cold.

Is it the clutches in the LSD making the noise or do you guys think a bearing is going bad??

 

You didn’t mention what oil you were using in your set-up or what spring rating in the differential you went with, but one thing that is required with the clutch style posi’s is the use of a limited-slip additive. When you resealed the rear cover, did you make sure to add the additive? Also, while the standard spring rating in the Eaton’s are 400lbs with Kevlar clutches, there are 200lb and 800lb springs available, however the Kevlar clutches are not normally used in conjunction with the 800lb units and eventually cause the clutches to start locking up as the gear oil wears. Usually, all it takes to rectify the issue is changing the oil and using the aforementioned limited slip additive.

 

I used Mobil 1 dino oil the previous time with a bottle of GM limited slip additive. After the cover leaked I replaced the fluid with the same combination. The spring rate for the LSD are the 400lbs springs and Kevlar clutches. I'm stumped on this one... Thanks bud