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Gear pattern

Napoleon1991

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Im changing to 3.55 gears in my 741 diff. Never done this before so im looking for some advice on how the gear pattern looks. I have .090 shims behind the pinion bearing. Any help would be appreciated.

image.jpg image.jpg image.jpg
 
I don’t know all these terms, heel, toe, etc but I like it ‘top to bottom’ , which is pinion shim. But it looks like it could stand to be deeper in the ring gear. I think that’s backlash, you’re already at .008”, if the spec on the gear says you can go tighter, I would try 6 or 7, see what that looks like.

I’ve only done a couple of these, I’m far from an expert. Hopefully one of those guys will chime in.
 
I would agree with the previous comment. I've only done a few diff rebuilds and it looks like you need to get a little deeper into the ring gear so your pattern is closer to the root of the ring gear tooth. As long as you can stay within the backlash spec.
 
I checked the spec and .008 backlash seems to be correct. Just wanted to post a couple more pics before I disassemble to add a shim. The pattern looks pretty good to me, so I don't think I need to add much.

IMG_5378.JPG IMG_5377.JPG
 
Try 5 thousands more. Back lash looks pretty good to me.
 
The bottom picture looks better but if I'm looking correct it is reverse. The top picture looks like forward, but looks too far up on the ring tooth that's what I would want to correct. I do not do this enough to be comfortable, but it would be my focus. FWIW
 
Here it is shimmed .005 more. Backlash is .007. First pic is the drive side of the teeth.

image.jpg image.jpg
 
The patterns are rarely perfect on drive and coast. They also really seem to vary or be irregular around the crown wheel these days. It can be a bit of a crap shoot.
Drive is looking better/pretty good.
Experiment with a little less backlash perhaps?
Just play around until you get the overall best pattern. I have found I get the best pattern if there is about 25 thousands of the marking paint below the contact pattern at the root of the tooth on the drive side.
Changing the pinion shim on a Mopar diff definitely a bit of a pain.
 
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