Offroad Trailblazers and Envoys

PML Cover for our Rear End

G80, GU6, GT4, GT5, WTF? This section is for gearing and driveline stuff.

by AzEric » Fri Feb 08, 2019 3:57 pm

Just figured I'd post what I found out after reading about, then speaking with a helpful applications person at PML (

The proper cover for either the 8.0 or the 8.6 rear is what they call the "GM Torsen" rear cover, part number 11035 shown here:

Note that it will (barely) clear the trackbar.

I am not advertising for them, but I have been reading and looking for quite a while for the proper aftermarket cover for our rear differentials, and it is the only one I have found. It is a cast aluminum cover, so the metallurgist in me is skeptical about using it for our offroad applications vs the Purple Cranium half spider. I welcome any input and real-world experience inputs!


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by DirtyBacon04 » Fri Feb 08, 2019 11:05 pm

I've always been kinda put off by aftermarket diff covers. They seem, for our platform anyway, more of a bling accessory than actual function. I've been sticking with the factory cover and a purple cranium. The gears are splash lubed, and when up to speed the design of the factory cover allows for a nice circular flow of oil to get all over the gears. Those flat faced aftermarket covers don't provide that same splash pattern.
This Banks video explains it better than I.
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