Rear diff gear pattern

Question for the diff specialists:
Gm 7.5" Rear diff with a 10 bolt cover.

New ring and pinion, pinion backlash is at 0.010 inch, got the right pinon (15 inch/lbs) and carrier preload.
Pinion has the standard shim which is 0.35"
Backlash Is a tad loose and needs to be a little tighter with another shim, most important for me right now is the gear pattern.
I think i am real close, on the other hand there are people who do this for a living and i am sure they can give me some advice or at least point me in the right direction.

pontiacgp said:

I would bring the backlash down to 8 and check the pattern again. The pattern you have now looks pretty good.

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I knew backlash is a bit loose so i will go and try to get it towards the .008 and see what happens, might take a while before i come back with pictures time is a bit short here.

Bonnewagon said:

Any factory manual that covers rear wheel drive has a section on tooth contact pattern. It will have examples of patterns and tell you what to do to correct them.

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You're so true on that, those patterns are all over the place,( and yes i have 2 books on the monte carlo) but... they don't tell you how to tweak a little like the guys do who have done diffs for a long time.
I am an instructor in pneumatic door systems,(especially train doors) and believe me, you can adjust a pneumatic door from the book, or take some instructions from me, i guess i can teach you faster how to do it then the book does.
And thats why i am asking here so the experts can give me some tips and hints on the matter, after all its my first time doing a rear diff.

Thanks for understanding, i will bring back the backlash to .008 i have bought the necessary tools to do the job right.
Even bought the beam type inch pounds torque wrench,and a dial gauge with a magnetic base, those tools are a must have for this kind of jobs and if treated nicely will last a lifetime and then some.

Click type torque wrenches for ring gear bolts and bearing caps from work and even the diff oil is from my work as they do gear cases for trains. (Shell Spirax S4 AT 75W-90) And believe me nothing but the best as those gear cases do a million km and the oil has to last for 15 years before its renewed
.
I have a nasty habit of wanting to try to do things myself, i have a broad mechanical background so wrenches are no strangers for me.
Only sometimes its best to ask the guys who know, so i don't F up some expensive gears.

I am using a standard rear diff (GM 7.5") from a chevy monte carlo, this spare diff was junk.
I have a TH200-4r that has to go under the MC to improve mileage.
Downside was i needed a different gear setup on the diff, this is just a cruiser not a race car.
So i am overhauling the rear junk diff with new bearings and seals, 3.42 gears to make the most benefit of the TH200-4r.