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Old 11-12-2010, 11:35 PM   #1
kanuck
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Decoding 1974 posi gears

Is there a way to ID my gear ratio by code so I don't have to take the rear cover off?
Original code from the fender is C-80. It is a 1974 14 bolt corperate with the corporate 10 bolt front.

This is from the parts truck I picked up last week. Was a one owner truck that was parked in 2001 and the owner passed away in 2008.

Bought it mostly for the doors, but it has a great dash pad, tach dash and full interior trim. Cab looks decent for the most part, will need the inside rockers redone as there is rust on the underside. Truck was cleaned up and repainted in the early 90's. Frame is rusted out totally in the rear.

Other question is, "will it be a pain in the butt using a 4x4 cab on a 2 wd. I know it has the tall tunnel, but it also has cab lights. Any other differences I should know about?
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Old 11-13-2010, 03:45 AM   #2
kanuck
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Re: Decoding 1974 posi gears

Doing a little searching on the net brought me to a G 80 code which could be if I read it wrong, but all that showed was that the rear is a POSI.
Is there a separate location on the tag for the ratio?

Thanks,
Hagen
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'67 Firebird Convertible...all done stock
'70 LWB 350 on propane...beater
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Old 11-13-2010, 08:48 PM   #3
russgt
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Re: Decoding 1974 posi gears

Check in the glovebox, there should be some more axle info. Yes the G80 code has meant posi or locker in the trucks for quite a few years. The truck should have a dana 44 front and not a 10 bolt, if it is a 10 bolt it was swapped in from a newer truck.
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Old 11-14-2010, 09:46 AM   #4
LONGHAIR
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Re: Decoding 1974 posi gears

G80 is a Govlock that wasn't used in trucks that old. Something must have been swapped at some time.

What is so wrong about pulling the cover off?
This question comes up a lot...and I really don't get it. It's not hard or expensive and it really should be "the way" to figure this out. Anything could have been installed over the truck's lifetime and then you see what condition it is in. Then even if everything is perfect, it still got the fluid change that it deserved anyway.
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Old 11-14-2010, 10:06 AM   #5
russgt
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Re: Decoding 1974 posi gears

My 76 has option code G80
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Old 11-14-2010, 09:53 PM   #6
kanuck
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Re: Decoding 1974 posi gears

I got the code number off the option tag that is like the on that is in the glove compartment on my 1969, but on this 1974 it is on the top of the drivers side inside fender. Frame is rotted in the back and was trying to stay out from under the rear.
This is a one owner truck that seems very original and even found the owners note book where he wrote down the mileage of all the oil changes, belt changes and services of any sort.
Was hoping to sell the front and rear axle together to get back a bit for this parts truck as the rest will head to scrap metal.
Keeping, cab, doors, interior and grill assembly. Rest is pretty rotted.
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'67 Firebird Convertible...all done stock
'70 LWB 350 on propane...beater
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