8 3/4 Rear Axle Noise Question

hunt2elk

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Hope you have better luck than me. Everytime I have had gear noise, no matter how few of miles were put on them, the only fix was new gears.
 

Rusty34

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20220510_123549.jpg


Found one more picture that shows the numbers stamped into the ring gear at a slightly different angle. The number looks like it might be a Chrysler factory part number for a 3.23 gear set.

I will go back over and look inside the splined axle bores to see if there are any buttons in there. I'm now thinking it's possible metal particles might still be on the gear teeth and causing the erratic back lash readings we saw so we will check that again.

Also, would it be practical to start looking for a couple sets of OEM Chrysler wheel bearing kits to go back to tapered roller bearings with an adjusting nut in the RS retainer plate? And, is there anything else I should get a picture of and post while I am over there tomorrow?
 
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dvw

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I don't like .004" difference in backlash. As far as pinion depth run a pattern check. That'll tell you the story. If the gear set has been run set-up incorrectly it may never be quiet. I'd be pulling the ring gear off and see if the carrier has runout on the mounting face. As far as the thrust block. As long as it isn't pressing against the axle shafts when they are bolted in tight, it can stay. All depends on the length of the axle shafts. If you can get the backlash in spec then pattern check.
Doug
 

5.7 hemi

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That rear was getting hot with that small of backlash. Things grow when warm, I like .006-.011 for the street.
 
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Cranky

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I don't like .004" difference in backlash. As far as pinion depth run a pattern check. That'll tell you the story. If the gear set has been run set-up incorrectly it may never be quiet. I'd be pulling the ring gear off and see if the carrier has runout on the mounting face. As far as the thrust block. As long as it isn't pressing against the axle shafts when they are bolted in tight, it can stay. All depends on the length of the axle shafts. If you can get the backlash in spec then pattern check.
Doug
I've had ring gears that had that much run out before and yet the diff ran within .001. It kinda makes me wonder what's going on with gears coming from all over the world these days.
 

khryslerkid

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It kinda makes me wonder what's going on with gears coming from all over the world these days.

Got that right.

I recently installed a set of Motive Gears in my Dakota 9.25. Couldn't get a decent pattern, the drive side being higher than the coast. I went from one end to the other with pinion depth and backlash. Even sent Cass pics asking what he thought. Ended up with just a good drive side pattern and maximum backlash. It has the slightest wine on decell. After 400 miles it's getting a little quieter. It's definitely what we're dealing with today.
 

Cranky

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Got that right.

I recently installed a set of Motive Gears in my Dakota 9.25. Couldn't get a decent pattern, the drive side being higher than the coast. I went from one end to the other with pinion depth and backlash. Even sent Cass pics asking what he thought. Ended up with just a good drive side pattern and maximum backlash. It has the slightest wine on decell. After 400 miles it's getting a little quieter. It's definitely what we're dealing with today.
I have a set of Motive gears in my diesel with probably less than 500 miles on them. I can hear them whine slightly starting at 55 and it goes away once past 65. Thing is, 65 is about my max speed is these days. Maybe I should put a good load on them.....except I don't feel like doing another in the chassis gear job if they get worse but got a feeling they will anyways. I always heard people gripe about Richmond gears but never had a set of them make noise. And what's in your Dakota that made it come with a 9.25 or did you install that size rear end?
 
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