New gear setup howling

[JohnKcj5]

On jack stands in second gear at idle rpm, I can hear the diff whining. So I pulled the differential cover again to check things out. Ran the gear pattern again and checked the backlash. For some reason the backlash jumped from .007 to .015. I know that's no good. Pinion preload set to 20 in.lbs. But I'm wondering if the gear pattern is off and also a part of the problem. Am I too deep? Hopefully you can see the pic by grabbing this URL. I still can't get pics to post.
https://photos.app.goo.gl/hiMaZygrSisrSFYR8

 

[RiverandSand]

Can't see the link, says it's invalid.
Do you blue the ring and pinion? The pattern should be centered on the ring gear.

 

[JohnKcj5]

I don't get it with this site. All the formatting buttons are dead. Can't insert smiles. Nothing. Anyway, I said I rechecked the gear pattern. I know it's supposed to be centered. I've studied the images all over the net. Some of it seems to be subjective. Some like a "deep" look. Maybe this google link will work. https://photos.app.goo.gl/hiMaZygrSisrSFYR8

 

[Belizean]

2nd link worked great

 

[RiverandSand]

Great I see it now. Looks like the pinion needs to be shim ed out a couple of thousandths.

 

[JohnKcj5]

Great I see it now. Looks like the pinion needs to be shim ed out a couple of thousandths.

That's the advice I'm looking for. Thanks. Not sure how the backlash loosened up. I took it in and out between the setup race and final set up. It measured the same even after installing the crush sleeve. Something seems to have settled.

 

[Patrick]

Hopefully your howling issue is resolved. Crush sleeves are disposable and should not be reused, and belong in the factory production line for quick assembly. In the future, delete it and shim as necessary to achieve the right pinion depth and preload. Good luck.

 

[JohnKcj5]

Hopefully your howling issue is resolved. Crush sleeves are disposable and should not be reused, and belong in the factory production line for quick assembly. In the future, delete it and shim as necessary to achieve the right pinion depth and preload. Good luck.

Yea, I've got an extra crush sleeve. Believe me, I spent more time reading than turning wrenches on this. But I dialed in the pinion bearing preload to 20 inch pounds. Spec is 15-25. I didn't mention that the housing around the pinion bearings was pretty warm to the touch. Thinking about this, I'm going to pull everything out but the pinion and do a quick test. If I have noise, then I'll readjust to the low end of the torque spec. I did oil the bearings before installation. I'll follow up with you guys.....

 

[JohnKcj5]

UPDATE:
The 'howling' is coming from the Eaton Truetrac. I pulled both axles out and slipped one in just far enough to engage the helical gears in the differential. This ruled out a wheel bearing. When I give it a good spin, I can see the gears turning and hear what sounds like a scary wind howl. I've read where eaton said it's normal and if they adjusted it, it would weaken it. Probably quiet down after some use. With that said, I also found that the inner pinion bearing does not like 18 inch lbs of pre-load. I pulled the differential and did a test run for a couple of seconds. The inner pinion bearing starts chirping and I'm sure making more noise on the street. It's generating a little heat even when the diff was full of oil. I backed it off to 12inch lbs and the chirping went away. Both bearings are wet. Bottom line is I'm going to have to set the preload where the bearing tells me. Unless I've got a bad bearing. I don't see any indications of a bad bearing. It spins smooth.

 

[Lumpy Grits]

That gear pattern is way to 'deep'.
What diff oil are you using?
IMHO: Get away from the crush sleeve.
Gary

 

[Patrick]

I agree with LG. You have to address this first by moving the pinion away from the ring gear to more or less center the mesh point on the drive side of the gear (don’t worry about the coast side).

I am worried about the heat build up and the chirping you mentioned. Take the pinion back out (you have to anyway to reduce pinion depth) and make absolutely sure the outer bearing races did not slip on the axle housing. Keep in mind that you cannot adjust pinion bearing preload using a crush sleeve, it is predetermined by the crush sleeve.

 

[JohnKcj5]

That gear pattern is way to 'deep'.
What diff oil are you using?
IMHO: Get away from the crush sleeve.
Gary

I'm running 80w-90. That's what Eaton specs out. I'll remove some shim and get the pattern to move more towards the top of the tooth. I noticed I'm getting more of an oval shape contact patch than the pictures on the net. One mistake I made when I set up the gears is not putting enough resistance on the gears to get an accurate contact. What you see in the pic is after I tore it back down and used the parking brake for resistance. The pattern looks a lot different now. Live and learn. Thanks for the advice.

 

[JohnKcj5]

I agree with LG. You have to address this first by moving the pinion away from the ring gear to more or less center the mesh point on the drive side of the gear (don’t worry about the coast side).

I am worried about the heat build up and the chirping you mentioned. Take the pinion back out (you have to anyway to reduce pinion depth) and make absolutely sure the outer bearing races did not slip on the axle housing. Keep in mind that you cannot adjust pinion bearing preload using a crush sleeve, it is predetermined by the crush sleeve.

I'll remove the race and see if anything looks out of ordinary. I had to hit it pretty good to drive it in. Based on how tight the bearing race is on the pumpkin and how 'easily' the bearing drawed up on the pinion shaft, I'd bet if anything the bearing is slipping around the pinion.

I set preload by turning a breaker bar an 1/8th revolution against the crush sleeve and checking rotational torque with a dial inch pound torque wrench. I repeated this until I got 18 inch pounds.

 

[Patrick]

You are setting preload incorrectly. The pinion nut has its own torque setting value. When this torque is reached, the crush sleeve should have yielded the correct preload. But the pinion depth should have been set BEFORE final pinion nut torquing.

If your inner or outer races are spun, consider them ruined and get you a new set of bearings and inspect pinion for annealing damage. Consider enlisting the help from someone locally and avoid frustration if you have to. Good luck.

 

[JohnKcj5]

You are setting preload incorrectly. The pinion nut has its own torque setting value. When this torque is reached, the crush sleeve should have yielded the correct preload. But the pinion depth should have been set BEFORE final pinion nut torquing.

If your inner or outer races are spun, consider them ruined and get you a new set of bearings and inspect pinion for annealing damage. Consider enlisting the help from someone locally and avoid frustration if you have to. Good luck.

With all due respect, I think you're wrong on the crush sleeve. You continue to crush the sleeve until the preload is set. The torque on the pinion nut has nothing to due with it. You're thinking of the shim kit that replaces the crush sleeve.

I'll check on the the bearing races.

No, Sir. I will not consider buying help. I'll figure this out even if I have to buy another set of gears, or what ever. With all due respect, telling someone who asks for help to buy help is not helping. But thanks for the advice.

 

[Patrick]

Hey man, no problem. Didn’t mean to upset you.

 

[Lumpy Grits]

I've set up more than a few R&P's in my life.
Get rid of the crush sleeve and make a spacer to use with shins.
The crush sleeve you have is dead.
Back that pinion out.....
Gary