Dana gear setup help?

[INTMD8]

Hello,

I'm in the process of swapping a 3.54 for a 4.10 in my Dana. Used original gear.

The 3.54 was toe biased on the drive side and only .006 backlash when I took it out.

It was however completely quiet.

I first installed the 4.10 with the same shims and it was even more toe biased on the drive side and backlash opened up to .010.

I thought to get the drive side more centered I needed to remove pinion shim so I went from .0465 to .030. (removed .0165).

This opened up the backlash to .016 and I ran a pattern like that as I don't have a press at home to remove the carrier bearings.

This put the pattern at the extreme edge of the ring gear.

Any suggestions on where to go from here? Thinking I removed too much pinion shim as I don't think tightening up the backlash is going to fix the second pattern set pictured.

Thanks!

-Less pinion shim, .016 backlash-

 

[5.7 hemi]

I never consider the drive side pattern when setting up used gears (to an extent). Take .005 off the pass. side shins and move it to the drivers side and re-measure back lash. This should also get a better pattern on the coast side.

 

[john-9]

the pattern in the first 2 pics looks really good on drive and coast --under load ( driving ) the pattern will move up on the tooth --- maybe tighten up the back lash a bit (.006- .008 ) -- the shim change you did which was way too much ,, took the pinion gear set right out of its correct position with the ring gear ---- when you do pinion shim changes do them in .003 increments so you can see actual movement up or down and shape in the pattern.
i would run the pattern in the first 2 pics.

 

[dvw]

I agree with John 9. First pattern is close. The toe bias is a result of the pinion C/L machining in the housing. You wont change it much. .016:back lash is pretty loose. Go to the Yukon Gear website and read their tutorial on set up.its very good.
Doug

 

[INTMD8]

Thanks guys. I'll put the pinion back to original depth and tighten up backlash.


Edit- Reading the yukon gear setup page. Good info! They say to focus on coast pattern and being centered within the tooth face to flank rather than worry about drive pattern from heel to toe. (as 5.7 hemi mentioned).

That being said it seems maybe a little more pinion shim from my starting point would fix it as my first pattern is still favoring the face of the gear.

Slightly more shim would put it a little more centered and tighten up the backlash. (I think)

Will try and report back.

 

[INTMD8]

Have to say... I'm exhausted.

Tried the above which was add a little more pinion shim from my starting point.

Started- .046 I installed .049.

Backlash did tighten up to .009

Ran a pattern and it was not good. Coast side moved way to the heel of the gear and the drive side was off the edge of toe.

So. I pulled it all back apart, put the pinion shim to .045. Bought a 2 jaw puller which barely removed the carrier bearings and I swapped .006 from the passenger to driver side.

Don't have a press so pressed the bearings back on with the carriage of my 2 post lift and the weight of the car. Was actually much faster than using a press

So, ended up with .006 backlash (which is what the previous gear was at) and the following pattern.

Don't think it will get any better at this point. Does seem to be driving off the nose of the pinion gear but looking with a mirror, the coast side of the pinion is dead center.

Well, I'm going to give it a try. Thanks guys.

 

[5.7 hemi]

Now paint the ring gear, and put your hand on the carrier as you turn the yoke and see how your pattern moved. I bet it’s better with a bit of “load” on it.

 

[INTMD8]

I buttoned it up today and took it for a drive. Coast is silent. Tiny amount of noise at 60mph+ on drive.

Overall I'm still really happy. (and still quieter than the stock diff in my now sold Hellcat)

 

[6PKRTSE]

I started from scratch on my Dana 60 with a bare truck housing that I narrowed. I probably had it mocked up and disassembled 15 times before I got the shims and patterns where I needed them to be. It does take time and effort to do it right.

 

[Cranky]

I have a pinion depth mic and go by that. The drive side never looks right by never paid much attention to the coast side but have never had a problem so long as I went by what the indicator said. Problem now is that it doesn't work with a Dana 70 so I'm using a regular wide base depth mic and measuring from the bearing split line. The carrier bearing seat is a bit deeper than the caps so I'm having to account for that. And I'm placing the shims on the outside of the bearing instead of the inside so I'm not having to remove the bearings.