Can youu check this gear pattern please?

[COKE]

Good day

I need to finish my 12 bolts gear change(From 3.43 to 4.11) and i need a bit of help.

This is the gear pattern with a 0.032 shim/0.008 Backlash .I,m considering to run it,but not sure.

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However i have tried to a 0.005 thicker shim just to see what happens .This is 0.037 and 0.008 backlash.


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Would you run the first one?
Any input is very much apreciatted.

Thanks and happy new year.

 

[Hogback Fabrication]

Run the first one

 

[blazinzuk]

Yep the first one it is see that harsh straight line on the one with the .037 the line on the root of the tooth. Thats bad you don't want those harsh straight lines.

I don't know if you are using setup bearings and I am alot more anal on setups than alot of others but if its easy to do I would try to do a .034 or .033.

The setup you have is fine but like I said I like to play around a bit with em.

 

[COKE]

Thanks a lot for the replies

Blazinuk i don,t have a 0.034 pinion shim,i wish,the set i have jumps from 0.032 to 0.037.
However i,ll try to get more shims.

I,m using the old bearing for the tests.I honed it´s inner race a bit for changing the shims easily.
I hope that nothing changes when i install the new one.


Also would like to say that i was working with a 0.070" shims under the pinion until i found this page :
http://www.streetrodstuff.com/Articles/Drivetrain/Rear_End/Page_2.php

With 0.070" the pattern was centered in the tooth but it was very thin.
Thanks to that page i was able to understand why i was wrong,and to take those measures allowed to get me in the ballbark.

 

[Blue85]

The first pattern is OK, because the root to face placement is more important than the heel to toe. You can't always center it in all directions because there is really only one proper depth for the pinion (based on the carrier axis of rotation). So how the pumpkin was machined determines how well that pattern can center from heel to toe. The tolerance on gears is much better, so if you were to set up another gear set in that housing you would get a similar placement of the pattern.

 

[COKE]

Thanks Blue85, i,m only worried about what will happen when i mount the new bearing and torque the nut.I hope it doesn,t change.


What shim set can i order wich has a good range of shims?
The one i have has several 0.028 shims,several 0.032 and so on.
I would prefer to have shims with 0.002 increments,just to play a bit more as Balzinuk said in his post .
I have to order some parts from Summit now,and i was considering the one from Richmond maybe?

Thanks again

 

[Stomis]

The first one is acceptable but I would bring the pinion into the ring a tiny bit more.

 

[Blue85]

What I do in this situation is go to the local driveline shop and ask for a couple of shims of the right thickness. This can cost $1 or less as they keep boxes of used parts around. The shim doesn't have to be specifically for a 10-bolt axle. It just needs similar ID and OD and of course a thickness in the range you are looking for. If you look at the shim kits you buy, you will see that the ID and OD are really pretty sloppy. The only tight tolerance is the thickness of the stock they are stamped out of. Of course you have to find a shop that has parts on hand and will deal with little nickel and dime stuff like this.

If there is nothing available locally, then just order a kit with some thinner shims. If Summit doesn't list the thicknesses, go to the manufacturer web site.

Have you pulled the shims off the old pinion? Usually people use that as the starting point for the replacement pinion. If you didn't, that is another source of shims at your disposal. Or if you have some other differentials or gears laying around.

 

[COKE]

The old pinion was 3.43 ratio and had a single 0.029 shim.
I tried this shim but the pattern was too much top contact

Don,t matter to order another set since they are cheap,the trouble as you said before, is that they don,t list what sizes do they include,neither in the manufacturer web.

I t would be interisting to try a 0.034" shim for example.