Author Topic: Ring Gear Backlash  (Read 7319 times)

Offline Ronno6

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Ring Gear Backlash
« on: September 14, 2018, 10:45:34 AM »
I have seen this mentioned on older threads, but, rather than resurrect an old thread, I'll just ask:
1984 C-10 8.5" 10 bolt diff 3.73 ratio
I nave seen ring gear backlash specs listed as .003" - .006" from some sources, and  .006" - .010" from others (more prevalent,)
What is the wisdom of the crowd??
Thanks.
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Offline Henry

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Re: Ring Gear Backlash
« Reply #1 on: September 14, 2018, 11:31:03 AM »
Hi Ronno6:
My 1976 Overhaul Manual has .005-.008 inch for the differential you mentioned...I do not believe the gear ratio has anything to do with the backlash. You should look at the 1984 Overhaul Manual to see if the spec changed...the manual should be on the tech section of this forum or on the net somewhere.
Regards,
Henry

Offline Ronno6

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Re: Ring Gear Backlash
« Reply #2 on: September 14, 2018, 11:57:50 AM »
Regarding Henry.....good flick.

Thanks for the guidance.
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Offline Ronno6

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Re: Ring Gear Backlash
« Reply #3 on: September 14, 2018, 02:37:32 PM »
OK. Initial backlash measures .012"
I need to move the ring gear .006" closer to the pinion to achieve a good amount of backlash.

A side note: I had to reduce the thickness of the original left side shim by .003 to install.
Is this common, or should the original shim packs always be installable with a new carrier?

Can I check the engagement pattern at this time?
Or, will that change appreciably when I move the ring gear in ?

That is to say, if the contact patches are good now, will they change when I shim the ring gear?
« Last Edit: September 14, 2018, 02:56:50 PM by Ronno6 »
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Online VileZambonie

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Re: Ring Gear Backlash
« Reply #4 on: September 14, 2018, 03:49:59 PM »
You have to rob Peter to pay Paul. If you are removing thickness, you are reducing bearing preload.
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Offline Ronno6

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Re: Ring Gear Backlash
« Reply #5 on: September 14, 2018, 04:39:17 PM »
You have to rob Peter to pay Paul. If you are removing thickness, you are reducing bearing preload.

I understand that.
Question is, I suppose, could ther be a difference between the OEM open carrier and the Yukon Posi carrier??
If the two are exactly the same, then I should put the original left side shim back in.................

When I disassembled the diff I had to pry the carrier out of the housing.
Should that be necessary? Should it be that tight?
« Last Edit: September 15, 2018, 07:20:13 AM by Ronno6 »
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Online VileZambonie

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Re: Ring Gear Backlash
« Reply #6 on: September 15, 2018, 08:17:21 PM »
Yes, it should. Are you measuring side clearance?
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Offline Ronno6

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Re: Ring Gear Backlash
« Reply #7 on: September 15, 2018, 10:19:10 PM »
Yes, it should. Are you measuring side clearance?

Not as of yet. I could use an education,please.
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Online VileZambonie

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Re: Ring Gear Backlash
« Reply #8 on: September 16, 2018, 12:56:38 PM »
There are plenty of posts on the forum in regards to this subject. Keywords, pinion depth, backlash, gear tooth contact pattern should all yield some good results.



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Offline Ronno6

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Re: Ring Gear Backlash
« Reply #9 on: September 16, 2018, 03:50:10 PM »
There are plenty of posts on the forum in regards to this subject. Keywords, pinion depth, backlash, gear tooth contact pattern should all yield some good results.

That is true.
But, The only posts I can find that mention side clearance are the one you sent me and I replied to..a couple of posts ago.

I have achieved a backlash of .006" - .009" and a very good contact patch.
Now to disassemble to install the crush sleeve, set pinion preload, then reassemble and re-check.
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Online VileZambonie

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Re: Ring Gear Backlash
« Reply #10 on: September 16, 2018, 06:13:21 PM »
Side to side = carrier bearing preload. So if it's good then you will have good long term results.
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Offline Ronno6

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Re: Ring Gear Backlash
« Reply #11 on: September 16, 2018, 06:17:29 PM »
Side to side = carrier bearing preload. So if it's good then you will have good long term results.

There be no measurable side to side play....I have to tap the shims in, and have to pry the carrier out....
Hopefully
i am headed in the fight direction.
Thanks!
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Online VileZambonie

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Re: Ring Gear Backlash
« Reply #12 on: September 16, 2018, 06:31:27 PM »
You measure it by affixing a dial indicator to the side of the ring gear. Pry the carrier from left to right and right to left. The recorded measurement on the dial indicator is your side clearance. You will have to force it in and out unless you have a housing spreader.
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Offline Ronno6

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Re: Ring Gear Backlash
« Reply #13 on: September 16, 2018, 06:58:38 PM »
You measure it by affixing a dial indicator to the side of the ring gear. Pry the carrier from left to right and right to left. The recorded measurement on the dial indicator is your side clearance. You will have to force it in and out unless you have a housing spreader.

Gotcha.Thanks.
I'll check.
Bearing caps loose or tight??
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Online VileZambonie

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Re: Ring Gear Backlash
« Reply #14 on: September 17, 2018, 04:08:06 AM »
You measure with it properly installed and caps torqued to spec.
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