Author Topic: what dif is this?  (Read 5085 times)

Offline 1979C20

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what dif is this?
« on: February 08, 2011, 05:11:04 pm »
The RPO codes from the label in the glove box says g80 differential, but This looks to me like it would be an open diff. Can you guys tell me what it is? Sorry for how big the pics are.

« Last Edit: February 10, 2011, 04:30:01 pm by 1979C20 »
1979 SCLB C20 Q-jet 350 SM465 14b F.F. 4.10 G80
1989 GMC Suburban V2500 TBI350 TH400 4in lift 35's 14b SF

Offline zieg85

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Re: what dif is this?
« Reply #1 on: February 10, 2011, 04:32:57 pm »
Looks like a Gov-Loc to me...
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline Captkaos

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Re: what dif is this?
« Reply #2 on: February 10, 2011, 04:37:23 pm »
that is a 14 bolt axle.  How many "window" holes are in it at the base of the gears?  4 = open, 3- gov loc (G80)

Offline 1979C20

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Re: what dif is this?
« Reply #3 on: February 10, 2011, 04:49:48 pm »
I know its 14 bolt, I'm not sure on the number of holes. But I do know that when I took my truck off roading, The rear tires are both spinning. so I know it is not open carrier. I dont know when the tires are both spinning. I'm trying to figure out if its a locker or limited slip. I'm thinking its the g80 locker, as that what the options sheet said. But I figured it could have been swapped out before. How does the g80 work? I read online somewhere that it disengages at 25+mph. so, from 0-24 the tires are locked up tight?
1979 SCLB C20 Q-jet 350 SM465 14b F.F. 4.10 G80
1989 GMC Suburban V2500 TBI350 TH400 4in lift 35's 14b SF

Offline Captkaos

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Re: what dif is this?
« Reply #4 on: February 10, 2011, 05:40:31 pm »
IF it is a gov-loc it will have 3 cross shafts instead of 4.  The gov-loc works by sensing a 100rpm change between the axles and will lock both when slippage is detected.  It will stay locked until you let of the gas.  If you are driving faster than 25, it won't engage.  Under 25 with no slippage it is open.

Offline topp

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Re: what dif is this?
« Reply #5 on: February 10, 2011, 07:45:06 pm »
What Capt. Said...

They tend to go boom eventually...
'90 Suburban TBI 350