Looking For Gear Pattern Input

Morks

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Hey guys, doing my first regear here. This is a pattern from a 2003 rubicon 44 rear. This pattern is from a backlash of 8 thousandths. Looking for advice on what to change, thanks.
 
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Can you post some pics? Your pattern almost looks shallow on the coast and deep on the drive. Do you have the bearing caps torqued?
 
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I will post some pics in 2 seconds. I did not fully torque bearing caps, Just used a drill with a clutch, Like @hosejockey61 does in his regear vids.
 
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Drive side is on the left, and the coast is on the right. @Blackjack @hosejockey61
 
When you see hard lines at the bottom of the pattern/marking compound, that's a good indicator that you're too deep. To my eyes - and not knowing what adjustments you've made so far - it appears that you're a tad deep based on the clear line a the bottom of the marking compound and where the pattern is centered (it is very heel heavy). I would pull ~0.010" out of the pinion shim and see where you stand.

Also, make sure the caps are properly torqued each time. We're talking about the differences in contact due to 1/1000th of an inch difference in shim stack heights, so consistency is key, especially if you are checking pattern with a carrier that has 0.000" preload in the saddle.
 
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When you see hard lines at the bottom of the pattern/marking compound, that's a good indicator that you're too deep. To my eyes - and not knowing what adjustments you've made so far - it appears that you're a tad deep based on the clear line a the bottom of the marking compound and where the pattern is centered (it is very heel heavy). I would pull ~0.010" out of the pinion shim and see where you stand.

Also, make sure the caps are properly torqued each time. We're talking about the differences in contact due to 1/1000th of an inch difference in shim stack heights, so consistency is key, especially if you are checking pattern with a carrier that has 0.000" preload in the saddle.
I'll take out 0.01" and torque the caps down and see where it puts me! I will post pics shortly
 
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I'll take out 0.01" and torque the caps down and see where it puts me! I will post pics shortly
Be aware that you'll probably be OVERSHOOTING the pattern the other way taking out 0.010" - and this is the point. You want to confirm that the pattern is shifting as you would expect it to the other way. If it doesn't, that's an indication that something else is the problem (pinion bearing not seated properly, race not all the way in, etc.).

From there, you can use what you know from the initial pattern and the -0.010" change and go from there. If you've made a big step away from a centered pattern, add back in 0.006"-0.008". If you're not too far away, add 0.002-0.003". Based on the hard line and the difference in coast/drive side patterns, I suspect you're further away from ideal pattern than some may be thinking. My guess is you'll be adding in ~0.003" or so for the final pattern (or about -0.007" from where you are now).
 
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Apparently, my micrometer decided to take a poop today and isn't working... (yes I put a new battery in lol). But this is removing the thinnest shim that was in there. Going to remove another fairly thin one and put back another one that is slightly thicker than both. Unless this is a halfway decent pattern.



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Without the micrometer, I can't say for either how much I took out, etc.. but I know the shims and have them placed accordingly on my table. Here is another pattern within backlash spec with fully torqued bearing caps.


image1 (5).jpeg
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Apparently, my micrometer decided to take a poop today and isn't working... (yes I put a new battery in lol). But this is removing the thinnest shim that was in there. Going to remove another fairly thin one and put back another one that is slightly thicker than both. Unless this is a halfway decent pattern.



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That looks like garbage.
 
Don’t guess on the shim stack changes - get your micrometer working again. To my uneducated eye it looks like your guess resulted in pulling out way too much since your pattern is now coming off the toe and is way too shallow. I think that prompted HJ’s garbage comment, but I certainly defer to him as he knows his stuff.
 
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Don’t guess on the shim stack changes - get your micrometer working again. To my uneducated eye it looks like your guess resulted in pulling out way too much since your pattern is now coming off the toe and is way too shallow. I think that prompted HJ’s garbage comment, but I certainly defer to him as he knows his stuff.
Yeah going to grab another one today. Don't really have any other shims though, just what came in the min install kit from REV, so if I cant get it with what I have I will probably need to get some more shims.
 
Yeah going to grab another one today. Don't really have any other shims though, just what came in the min install kit from REV, so if I cant get it with what I have I will probably need to get some more shims.
Your movements are not limited to the thickness of your smallest shim. You make small changes by changing the combination of the shims in the stack. That is why it is a good practice to measure and mark all of your shims as it makes the process easier. Even with that I still measure the thickness if the entire stack with each change I make.
 
Your movements are not limited to the thickness of your smallest shim. You make small changes by changing the combination of the shims in the stack. That is why it is a good practice to measure and mark all of your shims as it makes the process easier. Even with that I still measure the thickness if the entire stack with each change I make.
Absolutely, not much variance in shim thickness that came with the kit. That is why it was close before making different stacks and just guessing threw it off haha. Will have some different patterns tonight or tomorrow.
 
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