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Hey dfrates,
IMHO (key word here is OPINION) it looks like you might need to DEcrease your Pinion Shim as it looks a bit deep on your Drive and increase your backlash as your a bit low (towards the axle) on the coast side. You're not that far off so do small amounts for each and expect you may have to do it again to "nail it". The idea is to "float" in the centre/ middle of the face on both drive and coast. Getting it right or close to right is worth the effort.
Easy to say, PIA to do but look at it as something fun to do rather than a chore and you'll enjoy the result.

There are good knowledgable guys on here that may see something I've missed though so standby....
 

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Based on the contact patterns shown in post #1, I agree with Tacocaster... but you are very close to the desired set-up. I would go with .003 decrease in pinion shim and see were that gets you. Try to keep your backlash within manufacture's recommendations when increasing the lash.
It took me 3 times to change my pinion shim to get a decent pattern when I set up my 12 bolt.
My pinion was not deep enough and I had to increase the pinion shim.
Below are some examples of the Drive and Coast patterns I got with the different pinion shim depths. All patterns @ .009 backlash.
399504

399505

dfrates, How are you turning the ring gear to get your contact pattern?... are you turning the pinion yoke?
You will get a "more defined" contact pattern by inserting one of the axles into the differential and turn the axle in both directions to move the ring gear (You may need something to turn the axle. I used a 1" x 2" x 24" long piece of wood positioned between the wheel lugs). I would also recommend only using the gear marking compound on 3 or 4 teeth... but on 4 different places on the ring gear.

The chart below may also be helpful. "Drive" side contact pattern on ring gear.
399501
 

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Discussion Starter #4
Thanks Guys, I was turning using the yoke. I will try using the axle tomorrow and recheck the pattern. What do you recommend for backlash. I am at about .007.
 

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Before you change anything, try turning the ring gear with the axle to check your contact pattern... adjust as needed.

Was there a backlash spec printed on the ring gear? I would keep the backlash within manufacturer's specs.
If .009 backlash is within specs, you may want to try that to see if you gain a better contact pattern on the ring gear if your new contact pattern (turning ring gear by axle) is similar to the original photos you attached to post #1.
 

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Discussion Starter #6
Thanks Guys,
I re-ran the pattern turning the axle and this is what I have. I have about .009 backlash. Let me know your thoughts. I appreciate the help.
 

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You are very close!... and a more uniform/defined contact pattern when turning the ring gear with an axle.

Heel to Toe pattern looks a little better with the .009 backlash, but the pinion still looks slightly deep into the ring gear.
I would decrease pinion shim thickness by .003 and reset with same .009 backlash and recheck contact pattern.
Note: Be sure to take notes on all shim pack thicknesses with your current set-up.
 

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Hey dfrates,
IMHO (key word here is OPINION) it looks like you might need to DEcrease your Pinion Shim as it looks a bit deep on your Drive and increase your backlash as your a bit low (towards the axle) on the coast side. You're not that far off so do small amounts for each and expect you may have to do it again to "nail it". The idea is to "float" in the centre/ middle of the face on both drive and coast. Getting it right or close to right is worth the effort.
Easy to say, PIA to do but look at it as something fun to do rather than a chore and you'll enjoy the result.

There are good knowledgable guys on here that may see something I've missed though so standby....
I agree with Tacocaster, that your pinion gear is a touch too close to the ring gear. Get a new crush collar and decrease one shim and see how it looks. You're not far off - check that your backlash is in spec as well.
 
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