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Old 02-04-2007, 11:05 PM   #1
xtreme80
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What rear end gearing do I have?

My truck is a 1980, came from the factory with a 350-4bbl/TH350. It's got a 12 bolt rear end, not sure if that's original though.

How would I find out what gears I have in the back?
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Old 02-04-2007, 11:52 PM   #2
Srubydo1986
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Re: What rear end gearing do I have?

look in the glove box it should still have a paper tag telling you if not beats me also i think it might be on the driver door

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Old 02-05-2007, 06:00 PM   #3
Captkaos
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Re: What rear end gearing do I have?

If it is anything but standard it will be listed in the glove box in the RPO section, if it is standard, it is most likely 3.08. There is a stamping on the axle, but I don't have the codes to decifer them...
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Old 02-05-2007, 06:10 PM   #4
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Re: What rear end gearing do I have?

I have the codes for the ring gear numbers but you have to take the cover off....
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Old 02-05-2007, 06:31 PM   #5
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Re: What rear end gearing do I have?

If you get in that deep you can just read them off the ring gear and divide them to get the ratio.
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Old 02-05-2007, 08:43 PM   #6
xtreme80
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Re: What rear end gearing do I have?

I'll just look at the RPO sheet. I don't think the 12 bolt came on the truck from the factory, but I'll just assume that it did!
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Old 02-05-2007, 10:42 PM   #7
Srubydo1986
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Re: What rear end gearing do I have?

from what i was told the 2500 2wd did have a 6 lug 12 bolts but i think it was in a later models not our years
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Old 02-05-2007, 11:10 PM   #8
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Re: What rear end gearing do I have?

my 68 4wd has 12 bolt with 3.73's
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1996 Z-71 - "huntin rig"
1969 C-10 LWB (SOLD) "Project flip that truck or else"
1993 Passport, F@rd 1-ton (SOLD)"Project Cousin Eddie"


My Garage Build "The 1,000 footer"

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Old 02-06-2007, 12:00 AM   #9
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Re: What rear end gearing do I have?

Quote:
Originally Posted by xtreme80 View Post
I'll just look at the RPO sheet. I don't think the 12 bolt came on the truck from the factory, but I'll just assume that it did!

12bolts came factory on all 73-80's. 10bolts started showing up in 81 and 12bolts were gone by 82...
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Old 02-06-2007, 01:50 AM   #10
xtreme80
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Re: What rear end gearing do I have?

Quote:
Originally Posted by Captkaos View Post
12bolts came factory on all 73-80's. 10bolts started showing up in 81 and 12bolts were gone by 82...


Oh! Then I'll look at the RPO sheet tomorrow and find out! Thanks!
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