Differential is moaning

[z71_perkins]

So my differential has been moaning and winning, kinda sounds like it has no fluid in it but it has plenty. Also it was also making the truck vibrate and shake until I replaced the pinion bearings but when I did that the winning noise got louder. The pinion is tight and not shaking around. I have A 2005 Chevy Silverado, 1500, z71, 4wd, with a GT5, 4:10 gear ratio, 6 lug

[Heavy 5.7]

"until I replaced the pinion bearings"

how did you set the backlash?

[Jsdirt]

^^^ Heavy took the wind outta my sails ....

 

Can't just toss them in and tighten - gotta set backlash AND preload. Even just tightening the nut too much will cause a howl on deceleration -- too loose, and she'll howl with your foot in it.

 

OR maybe I have that backwards, but one or the other is true. Been almost 2 decades since I messed with one.