On my 8.25 pinion I went from a .031 shim pack to .028, both with .008 backlash. Am I going in the wrong direction?

Trying to get this buttoned up this weekend.

Thanks!

Had an hour to kill before heading to the post office this morning, tried a big move to a .020 shim to see what the pattern does.

Watching the pattern moving about and I wrong thinking around a .024 would be spot on?

Looking at the movement on both patterns between the 31-28 and then 20 I think I would try the 24...

Ended up with .026 tonight, had a hard time getting a good picture.

Looks good to me right in the sweet spot.

It's amazing how much more tooth contact you can get with a small move. Even though it is slightly deeper in the root I like it better.
Doug

Maybe just a little more backlash???

Already on the loose side at .008

Cleaned everything well and assembled with crush sleeve, again backlash at .008

Ran car on the lift for several minutes, no noise noted.

Went out on a road test, gear whine at very light throttle 50-65 mph and then seems to go away at that point. Silent below, silent above. Very slight whine on decel from highway speeds.

Youtube video of noise, had a camera on the back seat. Ignore the electric fuel pump buzz.

https://youtu.be/mvQuNokQ6L4

Anything I can adjust or am I screwed? Diff was a little warm after 15 minute road test, about 230-250F I'm guessing by feel. Pattern was approved by vendor. I'm ready to set car on fire.

Some gears do whine a little.

Can not tell much from your audio

I'll try and do a better one tonight, its loud though when its in "the zone" louder than it should be.

Vendor told me to drive it 500 miles and then change the break in oil.

Never heard of a gearset getting quite over time.

https://youtu.be/0SZzoAEZSb4

Camera in trunk, short clip

Put about 30 miles on car tonight, no notable change.

Pattern looked pretty good. With this gear set my bet is this is as good as it gets.
Doug

What brand gears? I installed blue box Motive, load as all get out, am going to get a set of OEM Spicer gears to hopefully make it better

I'd still try opening back lash a little

Motive Gear C8.25-373

Not acceptable.

I'll try moving the backlash out a touch and see if there is any improvement but if this is "as good as it gets" with this brand... I'll have future plans to replace them with a different brand and take the loss.