67 C10 new Rear end question

[SilverGT3RS]

Setting up a new 4.10 rear end in my 67 c10 12 bolt. Eaton TruTrak and new Motive gears.

Everything is going together as expected, and right now, my bearing preload is running around 22 inch pounds with nothing but WD40 lightly sprayed on the bearings. I am running a solid Raytec spacer with around a .022 spacer installed.

A big problem for me is I’ve seen pinion bearing preload numbers all over the board. Numerous drivetrain places via google search are showing 13-15 inch pounds. A few Chevy manuals are showing 15-18 inch pounds. Even more confusing, Strange and a few other aftermarket gear manufacturers call for 20-25 inch pounds. Not sure why there’s such a wide gap between numbers.

Can I get some opinions on this?

[pjmoreland]

The higher numbers are for new bearings, and the lower are for used. The attached image is from the factory service manual.

20-30 in-lbs new
5-15 in-lbs used

[SilverGT3RS]

Originally Posted by pjmoreland

The higher numbers are for new bearings, and the lower are for used. The attached image is from the factory service manual.

20-30 in-lbs new
5-15 in-lbs used

Fantastic! I’m right around 22-23 inch pounds some I’m in good shape.

Thank you.

[jessemthompson]

I installed a new set of Yukon gears last summer and it called for 13-15 inch lbs. I have it set at 15 and everything is working great.

[SilverGT3RS]

Originally Posted by jessemthompson

I installed a new set of Yukon gears last summer and it called for 13-15 inch lbs. I have it set at 15 and everything is working great.

Yes Yukon calls for 13-15 inch pounds. Which is way less than the Chevy spec quoted above.

However I did refer back to the Motive assembly sheet and it says to use FACTORY specs. So, I’m sticking with the 20-30 inch pounds as referenced.