Author Topic: Identify my diff  (Read 4204 times)

Offline grey83c20

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Identify my diff
« on: February 06, 2016, 01:33:27 PM »
I have a very high level knowledge of differentials. Can anyone school me on how to figure out my gear ratio and if its an open or limited slip carrier?

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Offline grey83c20

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Re: Identify my diff
« Reply #1 on: February 06, 2016, 02:04:52 PM »
I have a 1983 c20. The rear end is a 9.5 inch 14 bolt.

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Offline zieg85

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Re: Identify my diff
« Reply #2 on: February 06, 2016, 02:32:38 PM »
at the arrow flat part of the ring gear, rotate it until you see the numbers.  A 41 9 would mean 4.56 for example
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline VileZambonie

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Re: Identify my diff
« Reply #3 on: February 06, 2016, 02:47:03 PM »
I have a very high level knowledge of differentials. Can anyone school me on how to figure out my gear ratio and if its an open or limited slip carrier?

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You mean don't?

Open differential

If you can't locate the stamp the formula is simple. Driven over drive. # of teeth on the driven gear divided by # of teeth on the drive gear to 1

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Offline grey83c20

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Re: Identify my diff
« Reply #4 on: February 06, 2016, 03:18:00 PM »
Not even a gov lok... Well that makes me sad. When I bought the truck I knew even less about the rear ends in these trucks. Thought I had a ff 10.5 14 bolt and limited slip. Now I have neither :-( lol thank you for the info though

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Offline Captain Swampy

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Re: Identify my diff
« Reply #5 on: February 07, 2016, 11:39:05 AM »
It is  full floating if it's a 14 bolt. That means the axle shaft doesn't carry weight, it only transmits torque.
1987  350TBI 700R4  4X4  4.56 gears  33" BFG All Terrain


http://forum.73-87chevytrucks.com/smforum/index.php?topic=32209.0

Offline enaberif

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Re: Identify my diff
« Reply #6 on: February 07, 2016, 11:46:29 AM »
Not even a gov lok... Well that makes me sad. When I bought the truck I knew even less about the rear ends in these trucks. Thought I had a ff 10.5 14 bolt and limited slip. Now I have neither :-( lol thank you for the info though

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If you knew diffs then you'd know to have a 14 bolt FF rear axle you would have a hub with 8 bolts to pull out the axles from the rim side.

Offline grey83c20

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Re: Identify my diff
« Reply #7 on: February 07, 2016, 08:30:44 PM »
Not even a gov lok... Well that makes me sad. When I bought the truck I knew even less about the rear ends in these trucks. Thought I had a ff 10.5 14 bolt and limited slip. Now I have neither :-( lol thank you for the info though

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If you knew diffs then you'd know to have a 14 bolt FF rear axle you would have a hub with 8 bolts to pull out the axles from the rim side.
Nope don't know much about them at all. That's why I'm here asking the questions.

http://www.gmsquarebody.com/forum/showthread.php?t=748

Hate to reference a different forum but in the name of correct information here is helpful info about the different 14 bolts gm made that I found after posting here. I have a semi float 14 bolt without hubs to remove the axels. 9.5 inch ring gear. 8 lug.

The full float 14 bolts had the hubs and 10.5 inch ring gears making them much stronger. Anyhoo case closed. I didn't have what I though I had. Thanks.

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Offline Irish_Alley

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Re: Identify my diff
« Reply #8 on: February 10, 2016, 11:43:12 AM »
they were referencing your original post it was a simple typo. but clad you learned, i wasnt sure by the pictures and 1" isnt that much but something didnt look right on about it being a ff. all the times i took mine apart something didnt click about it being a ff
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Offline Rattler12

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Re: Identify my diff
« Reply #9 on: February 10, 2016, 03:03:11 PM »
You may be disappointed that its an open diff........but don't be disappointed it's not a gov lock......I got one and am just waiting......
83 C-10 shorty 454, 5spd, 3:73 posi