How should I adjust this rear end gear pattern?

DVJ38

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Well this gear pattern isn't the best, but I am pretty sure the gear pattern isn't correct. Here are some pictures, tell me what you think.

-Pinion turning torque is set towards the upper range of the spectrum, right at 28 inch pounds.
-Backlash is set at .008 - .009 (right where I want it)
-I believe the old pinion shim on the 4.30 gear set was .023, and I have always heard that you should start at what shim you took out, and on average they were usually a .028 or .030. I put a combination of shims that measured out at .026 to start.

Here are the pics:

IMAG1137_zpsc7cf28ab.jpg

IMAG1136_zps9ef4abe1.jpg

IMAG1134_zps983c8165.jpg

IMAG1135_zpse1dd649b.jpg
 
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DVJ38

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Put the stock shim back in. 99 % of the time it works just fine.

Ya well I really don't know what the "stock" shim was. I bought the car with the 4.30's in it, and I don't know if that rebuilder reused the stock pinion shim or not. Also, I didn't take that pinion shim off, another person did, so I'm going on what they said. According to my findings, I have to reduce the pinion shim size though. I'm not sure if I'm correct in interpreting the pattern, and if I am, I'm not sure how much to decrease it by.

These are the sites I've been referencing:
8.8 Axle Gear Install
Back to the Homepage
So you want to install your own gears: A 'how to' 8.8 gear install - Ford Explorer Ranger Enthusiasts "Serious Explorations"®
http://www2.dana.com/pdf/5717.pdf

Hopefully somebody with some experience can chime in for me.
 

tt54l32v

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I would take some out as well, are both sets of pinion gears smooth on the gear end?
 

DVJ38

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It's been so long since I've even seen my 4.30's that I can't even remember lol. For some reason I remember taking pictures of the gear sets next to each other since they seemed difference for some reason, but now I can't find the pictures for the life of me!

Keep the opinions coming! I need this thing back together asap, as I need to move this month!
 

DVJ38

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I know some more of you guys have set up gears before and have done it successfully, without them whining afterwards. Help me out here.

Sent from my HTC Droid Incredible 4G
 

CJK440

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Are these new gears? If used, ignore the drive side and just read the coast side.

The problem with patterns, is they never look like the book. The trick is to make sure you aren't applying the marking compound too thick (thin it with gear oil) and make sure you preload one gear while turning the other to get a good read.

The trick is to be sure your pattern feathers out all around and doesn't leave a hard edge. If you apply the compound too thick, you will get a misleading hard edge showing down at the root of the ring gear tooth.

Sometimes you get a good pattern when the pinion picks up compound and applies it to the un painted ring gear teeth after a full rotation.
 

DVJ38

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Are these new gears? If used, ignore the drive side and just read the coast side.

The problem with patterns, is they never look like the book. The trick is to make sure you aren't applying the marking compound too thick (thin it with gear oil) and make sure you preload one gear while turning the other to get a good read.

The trick is to be sure your pattern feathers out all around and doesn't leave a hard edge. If you apply the compound too thick, you will get a misleading hard edge showing down at the root of the ring gear tooth.

Sometimes you get a good pattern when the pinion picks up compound and applies it to the un painted ring gear teeth after a full rotation.

Thanks for the reply. Sorry I forgot to mention, they are brand new Ford Racing 3.73's. I just dabbed a bit of gear marking compound on the center of each tooth and spread it, but still think it may have been too think. I'll try to mix it with gear oil and somehow get it even more thin. I had an axle in on one side and was spinning it back and forth with the pinion flange. I will also try turning it all the way around in one direction 10 times, then all the way around the other direction 10 times and see how the pattern looks.

Someone on coral just suggested that the contact pattern looks a little deep as well and that taking out some backlash would help with that and may get the pattern more towards the center of the tooth. I wanted to get it setup with .008-.009" to minimize gear clunk and so that it can have a chance to wear out and still be in spec.

I'll post up later tonight or tomorrow morning when I get a new pattern.
 
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encasedmetal

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I had to reshim about 8 times to get it where I wanted and I used all new stuff- did not reuse old shit. you just have to measure and reshim till you get it where you want it. I will say that the install pack was a little shy on what I needed shim wise so I had to order some .001 shims to get it there. here's my final marks
rear5.jpg

rear4.jpg
 

CJK440

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I had to reshim about 8 times to get it where I wanted and I used all new stuff- did not reuse old shit. you just have to measure and reshim till you get it where you want it. I will say that the install pack was a little shy on what I needed shim wise so I had to order some .001 shims to get it there. here's my final marks
rear5.jpg

rear4.jpg

Those don't make noise? I'm not a pro but like DVJ's patterns better.
 

Tabres

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My pattern was very similar to this and they whine slightly on decel. Nothing majorly annoying but it's there. Out of building the entire car myself, the gears were the only thing I wouldn't care about not ever doing again.
 

DVJ38

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Thanks for the input so far guys. I have new pictures of the pattern without making any shim adjustments. I believe the gears are making contact too close to the heel of the teeth on the drive and coast side, based on the location of the pattern and how quickly it starts on the heel end, but feathers out on the toe end. Take a look.

The first two pictures are when I tried mixing the marking compound with gear oil. It didn't work very well for the drive side, but I think it helped to reveal the coast side better.
IMAG1159_zpsbd43987d.jpg

IMAG1160_zps91165c44.jpg


Then I wiped that off and tried straight gear marking compound, as thin as I could get it. I think the drive pattern is too far down towards the heel of the teeth too.
IMAG1163_zps2a982cc4.jpg

IMAG1164_zpsea9c0dcd.jpg

IMAG1165_zps8216db31.jpg

IMAG1166_zps6222265c.jpg

IMAG1167_zps34dcfe34.jpg

IMAG1168_zpsba4f8344.jpg


So do you think it's worth it to try to increase the backlash .002, or should I change the pinion shim? Am I correct in thinking there needs to be some pinion shim thickness taken out? If so, how much .003-.004? Not really sure, it's trial and error for me, but hopefully I can get some more input.

Thanks guys.
 
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DVJ38

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Bump. I move Saturday and I'm hoping I can take my car with me lol. If not I'll have to rent a truck out for a second time for all my tools.

Try less backlash, and if that doesn't work try less pinion shim? Not sure...
 

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