2020-B1-9

Author Topic: Axle code help  (Read 161 times)

JAL71 TA

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Axle code help
« on: September 19, 2020, 02:09:05 PM »
Can anyone help me with this axle code? I have searched everywhere and cannot find anything more that this on my 71 TA diff.
3P2C312 upside down C i think. The stamping was on the passenger side but on the very top of the housing so its really hard to see. Needed a mirror flashlight and my phone to even see just this!
Jim
69TA
71TA 455
69GTO

firebirdparts

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Re: Axle code help
« Reply #1 on: September 29, 2020, 05:19:53 AM »
I've got a 71 shop manual, I'll look.  They gave some code information in there for service reasons, but the usefulness of that was pretty limited, as it's easier to identify axles by inspection than read the code, and of course it's "preseason" info as well. 
I want to be like Paul Kenny when I grow up
Joe Bays
1977 Y82 4-speed (red interior)
1978 Skybird 350
1978 Redbird 305
1979 Redbird 301 4-speed
1992 Lincoln Mark VII LSC/SE (red)
1970 Datsun Pickup
1953 Chevy pickup (converted 4x4)
1988 T-bird Turbo Coupe

firebirdparts

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Re: Axle code help
« Reply #2 on: September 29, 2020, 08:55:17 AM »
I've got a 71 shop manual, I'll look.  They gave some code information in there for service reasons, but the usefulness of that was pretty limited, as it's easier to identify axles by inspection than read the code, and of course it's "preseason" info as well.

I got absolutely nowhere with that.  The shop manual says that F-bodies in 1971 all have Detroit Gear axles (the cheap 8.5's with c-clips that we all know and love) and so the codes are supposed to be, with traction lock:
CAG 2.73
GYG 3.08
CJG 3.42
CGG 3.73
CBG 4.10

So that sure doesn't correspond at all. 

P in the shop manual refers to the Pontiac axle, and that does come into axle codes as the last letter (not used in my list here).  None of that stamping on your axle corresponds well to a date code either, using Chevrolet sources on the web.  There are a couple of sources that suggest date code formats. 
I want to be like Paul Kenny when I grow up
Joe Bays
1977 Y82 4-speed (red interior)
1978 Skybird 350
1978 Redbird 305
1979 Redbird 301 4-speed
1992 Lincoln Mark VII LSC/SE (red)
1970 Datsun Pickup
1953 Chevy pickup (converted 4x4)
1988 T-bird Turbo Coupe

Re: Axle code help
« Reply #2 on: September 29, 2020, 08:55:17 AM »
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