Contact pattern

[Dleslie212]

Was hoping somebody could take a look at my ring and pinion contact patter and telle what they think. First time doing this. I'm sitting about 5 thousandths backlash on the ring gear, and pinion is with 2 thousandths depth of what it calls for

https://imgur.com/gallery/PhIECi0

[mongocanfly]

Pinion to shallow..

[AussieinNC]

Yep, pinion too shallow...add a 20 thou shim and retest...you want pattern in center of ring gear tooth...

Once you get pattern correct, then set backlash...

[Dleslie212]

Originally Posted by AussieinNC

Yep, pinion too shallow...add a 20 thou shim and retest...you want pattern in center of ring gear tooth...

Once you get pattern correct, then set backlash...

So get pinion depth done first and then backlash. Gotcha. So I'm already pretty close to the depth marked on the pinion face. I'm using a level across the face where the diff cover sits, then using depth gauge of of my caliper, zeroing it, and then checking difference down from the same level to face of where the carrier brackets bolt down

Also, when checking rotational force of the pinion after putting in the new bearings and what not, is that checked while the carrier is in place? Or only while the pinion is in?

[mongocanfly]

Dont worry to much about the pinion markings..you need to get the depth set...I set the rotation torque with the carrier out..
You've got to have it all set together ..depth, backlash, rotation...
As you move the pinion deeper, you'll have to adj carrier shims as well...no way to tell what you have till it's all assembled

[Dleslie212]

Originally Posted by mongocanfly

Dont worry to much about the pinion markings..you need to get the depth set...I set the rotation torque with the carrier out..
You've got to have it all set together ..depth, backlash, rotation...
As you move the pinion deeper, you'll have to adj carrier shims as well...no way to tell what you have till it's all assembled

I'm going to go ahead and add 20 to the pinion tonight when it cools down a bit and then post a few more pics. Thanks for the info

[kwmech]

Looks too deep to me. Pinion has to come out to center the pattern. First pic is the coast side. I'd take out 10 then check it. May end up taking out more

[Dleslie212]

Originally Posted by kwmech

Looks too deep to me. Pinion has to come out to center the pattern. First pic is the coast side. I'd take out 10 then check it. May end up taking out more

Early this morning I ended up adding all my shims and all it kept doing was making the pattern worse. I finally took everything out except a single 20 thou shim and it's almost perfect now.

[kwmech]

Give us a pic

[Dleslie212]

Originally Posted by kwmech

Give us a pic

I’ll snap and post a few tonight after work. Hopefully it’s good. I tried heating up my pinion bearing in the oven and dropping it onto the pinion. I must have not had it hot enough, because it barely slid on and then instantly got stuck, so now I can’t slide the pinion back into place to get pics of the pattern. I have it sitting next to me in my work truck so I can drop it at a machine shop this morning to have it pressed the rest of the way on.

Whie I’m here - I bought a crush sleeve eliminator kit, and my install kit came with a standard crush sleeve as well. I’m leaning towards using the eliminator kit, but can’t really find any decent instructions on how to install it. Do I just torque the pinion nut to a certain setting with a certain shim, check bearing preload, and rinse and repeat till I have about 20 inch pounds? What torque should the pinion nut be set to?

Edit - after a little reading, I think I may have screwed up. I did all my shimming and checking contact patterns with my old crush sleeve in place. Is that a mistake? I’m thinking it doesn’t change the pinion depth, so it should be fine?

[mongocanfly]

I'd highly recommend the crush sleeve eliminator ...itll need shimmed to get the proper rotational torque..
Your Instructions should have your pinion nut torque...what axle do you have?

[Dleslie212]

Originally Posted by mongocanfly

I'd highly recommend the crush sleeve eliminator ...itll need shimmed to get the proper rotational torque..
Your Instructions should have your pinion nut torque...what axle do you have?

There were no instructions at all with the eliminator kit.
Rear end is a 12 bolt Chevy truck rear end

[mongocanfly]

https://m.youtube.com/watch?v=iZInF95qHX8

I think this explains it..having internet issues today..
Measure your old crush sleeve and start there with the eliminator and shims
With the eliminator I think about 125ftlbs on the pinion nut

[Dleslie212]

Originally Posted by mongocanfly

https://m.youtube.com/watch?v=iZInF95qHX8

I think this explains it..having internet issues today..
Measure your old crush sleeve and start there with the eliminator and shims
With the eliminator I think about 125ftlbs on the pinion nut

That video mostly just talks about the differences between the crush sleeve and eliminator, not really installation. Thanks though

[mongocanfly]

Ok ..I couldnt get it to play past the 1st 20 secs..

[mongocanfly]

I know there's some YouTube on it...but I cant get em to play..

[kwmech]

Originally Posted by Dleslie212

Edit - after a little reading, I think I may have screwed up. I did all my shimming and checking contact patterns with my old crush sleeve in place. Is that a mistake? I’m thinking it doesn’t change the pinion depth, so it should be fine?

Crush sleeve not needed at all to check set-up. Bearings need to be seated and a light drag on the pre-load to get gear contact pattern. That's all.

[Dleslie212]

Originally Posted by kwmech

Crush sleeve not needed at all to check set-up. Bearings need to be seated and a light drag on the pre-load to get gear contact pattern. That's all.

Not needed, it will it mess up my pattern and backlash if I happen to have put the old one back in during mock-up? I’m assuming no

[mongocanfly]

I missed the edit...but like kw said...leave the crush sleeve out during setup..

[Dleslie212]

Here is the latest pattern. Hoping it's good as I had the bearing pressed on this morning. Thoughts?

https://imgur.com/gallery/PGOsvjm

[kwmech]

I would have tried to go just a tad deeper-- maybe .003. Centered contact seems to be a bit off center to the outside. But that is way better than the previous pic. Coast looks good. Where did the backlash come out?

[Dleslie212]

Originally Posted by kwmech

I would have tried to go just a tad deeper-- maybe .003. Centered contact seems to be a bit off center to the outside. But that is way better than the previous pic. Coast looks good. Where did the backlash come out?

Backlash is pretty tight around 005. The manufacturer recommends 7-9. I didn't bother messing with that last night because I really really expected to hear that the pinion depth was wrong, but I can mess with that tonight and post more pics.

It's just weird that the pinion depth would be so far off what spec says. Spec calls for 2.751 and I currently have it sitting around 2.880 I think

[kwmech]

Originally Posted by Dleslie212

Backlash is pretty tight around 005. The manufacturer recommends 7-9. I didn't bother messing with that last night because I really really expected to hear that the pinion depth was wrong, but I can mess with that tonight and post more pics.

It's just weird that the pinion depth would be so far off what spec says. Spec calls for 2.751 and I currently have it sitting around 2.880 I think

Cannot really go for what is "ideal'' or what factory settings are. Too many manufacturers in the world with different machines grinding these things out. If you open the backlash a few thou it may fall into place

[Dleslie212]

Originally Posted by kwmech

Cannot really go for what is "ideal'' or what factory settings are. Too many manufacturers in the world with different machines grinding these things out. If you open the backlash a few thou it may fall into place

Here is the latest pattern as of five minutes ago. Depth is the same as before. Backlash is now at 006, that's closest I can get it to the 7-9 with the shims I have. My previous backlash was at 011, not the 004 I had told you before. So I tightened from 011 to 006 since the last link

Edit - I can do either 011 or 006 on the backlash. I figured tighter would be better. The previous pic link was at 011, the link below is 006

https://imgur.com/gallery/ynk6abR

[kwmech]

I'd say that's a keeper. Little tight on the back lash, but it will loosen up a little after everything breaks in. Do you have decent bearing preload on the carrier?