489 Gear noise and an odd thing I noticed

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65TerrorCuda

65TerrorCuda

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So while doing my green bearing conversion I noticed that it's nearly impossible to rotate my axles backwards with both wheels off the ground. I'm talking prybar hard, I can't physically do it without leverage. Forward is a bunch easier but still draggy. Trans is in neutral with driveshaft connected.

I do have a locker so both axles are turning the same direction, no differential action.
Gear noise I get at 25 and 33 mph on cruise and accel, goes away on decel. Used gearset, probably factory.

Here's the weird bit, cornering I get a loud whine from the rear end even with new axle bearings. Same as before green bearings. Front wheel bearings are all new.

Brake drums were off so no drag there.

Any ideas please let me know. I'm guessing worn R&P and/or carrier bearings. Hoping it's just a pinion depth adjustment lol

Edit: there were little metal flakes, 1 or 2 mm, that were copper-ish on one side and silver on the other in the lube sitting in the axle
 
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Time to pull the center section for inspection. See how much the pinion moves up and down and in and out. I'm thinking it sounds like the pinion crush sleeve has excessive crush, allowing the pinion depth to change with drive direction.
 
Garrett Ellison said:
Time to pull the center section for inspection. See how much the pinion moves up and down and in and out. I'm thinking it sounds like the pinion crush sleeve has excessive crush, allowing the pinion depth to change with drive direction.
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That makes sense, probably drop her out soon. Thanks!

Also just noticed this, related?
 
On a 727 and 904 the car is harder to push going backwards than going forward. Noticed this pushing cars inside garage.

By hand you can turn the output shaft much easier one direction than the other.
 
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413 said:
On a 727 and 904 the car is harder to push going backwards than going forward. Noticed this pushing cars inside garage.

By hand you can turn the output shaft much easier one direction than the other.
Click to expand...
Thanks for the reply! Glad to hear it's something normal.

Solid crush sleeve ordered wish me luck
 
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Update: I think I found the source of my gear noise. Insufficient carrier bearing preload. My fault when I did the locker install. Pattern looks alright

Picked up a solid crush spacer and it's too long. Got another one, a machined one, on the way from Dr. Diff. Crossing fingers.

Rotating pinion torque was 0 in/lbs so I'm wondering if it that was contributing too. Under torqued pinion nut?
 
Yeah, that means there’s no pinion bearing preload, which has you headed right to the “Chrysler Clunk” anytime the prop shaft loads the pinion. It’s the end result of the pinion getting up and down movement. Even with the solid spacer, pinion preload is necessary.
 
Garrett Ellison said:
Yeah, that means there’s no pinion bearing preload, which has you headed right to the “Chrysler Clunk” anytime the prop shaft loads the pinion. It’s the end result of the pinion getting up and down movement. Even with the solid spacer, pinion preload is necessary.
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^^^ Much appreciated ^^^
The solid spacer doesn't even compress the bearings enough to get rid of a ton of slop and is too irregular to trim in the lathe. Pinion nut was staked, so I don't think it's been off until now.
Thanks Garrett,
 
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