Advice on contact pattern

[squint_91]

I'm right in the middle of setting up my Dana 44, 4.56, ARB combo. I could use some advice on contact pattern before I go any further. This is my 2nd attempt at setting the inner pinion shims (increased from 0.042 to 0.045"), and 4th attempt setting backlash (currently 0.008-0.009").

Drive side

Coast side

Is the pinion too deep here? This is the difficult subjective part of the process where I have no experience.

 

[md21722]

I would say yes, Half moon shape with straight line on the root (bottom), means too deep so you need add pinion depth shims. I'd guess .004-.006 would get you there/almost there.

 

[Frank Z]

Straight line means the pinion is too deep, so start removing pinion shims.

 

[MoparManiac]

Yes you need to REMOVE inner pinion shims.

Go back to .042 and take a picture.

 

[md21722]

These guys are absolutely correct I stated shim change backwards.

 

[squint_91]

These guys are absolutely correct I stated shim change backwards.

Hah, that's what I figured you meant. Thanks for the advice! I can see it pretty clearly now after looking at the pictures for a while. The pattern at 0.042 was also too deep, I think I will remove 0.006" and check again.

 

[93blackxj]

Everyone has an opinion... Big tires run it a little deep, won't hurt a thing.

 

[squint_91]

I've seen a couple people mention that running a little deep is ok, which is a little surprising to me. But I get the rational - the case deflects under stress. I spent more time shimming and I think I got it pretty dialed in. This is really not as hard as some people make it out to be (with the proper tools anyway)

B/L sits at 0.007-0.008

 

[wavingpine11]

That looks really nice. Good job!

 

[wavingpine11]

Just wondering--did you have to pound out/pound back in the inner pinion bearing race each time you adjusted? I used a setup race recently but the results didn't match the final result when I swapped in the actual press-fit race.

 

[twinhauler]

Pattern looks great after your little adjustment. Good job. Just takes time to dial it in right! Run it!

 

[squint_91]

Thanks! Very satisfying to get results after poring over threads and pictures, building the damn case spreader, and buying all the tools.

I used a set up race for the inner pinion bearing that I could remove by hand. I haven't taken a final pattern yet, but my backlash tightened up by 0.002 after installing the new race so I need to get that back in spec first.

 

[squint_91]

I've been running this axle for a few months and put almost 2,000 miles on it. I followed the break in procedure and changed the gear oil twice. Both times, the magnetic drain plug has looked like this:

Is this pretty normal? The stuff stuck to the drain plug has an extremely fine texture, like mud. I wonder if you would notice this dispersed in the oil if you didn't have a magnet in there. Here are a few more pictures with the diff cover off:

 

[trippled]

Did you have any bearing failures or metal in there before? That stuff can be extremely hard to get out. I'd say some is normal, but if the oil starts getting glittery too you may have a problem.

 

[xcm]

Run it, then have a nice day.

 

[squint_91]

Did you have any bearing failures or metal in there before? That stuff can be extremely hard to get out. I'd say some is normal, but if the oil starts getting glittery too you may have a problem.

I totally cleaned out the housing, but it's possible there was some lingering stuff in there. I'm just going to keep running it, it's super smooth and no noise at all soooo I guess it must be normal.

 

[squint_91]

Alright it's time for the front D30/ARB. Any input on this pattern? Specs are IP 0.054", RGS 0.020", NRGS 0.062", 0.007-0.008" backlash, and roughly 0.005" carrier preload per side.

 

[trippled]

Run it.

 

[mechbullxj]

A compare contrast photo. Has some gear whine and pinion pre-load is tight, although I'm going to run it 500mi. and re-do it. It is the 8.25" rear with 4 56: gear set, wanted to show.

 

[squint_91]

Run it.

sweet :greensmok