identifying rear gears
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Joined: Sep 2002
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From: Epping NH
identifying rear gears
We dropped the rear end on the 69 yesterday and have the differential power washed and scrubbed. I believe I have identified the build date stamped into the pad which shows 1A0 9 26 69 W. Looks like Aug 26, 69 (my car is a Oct 69 vehicle).
There is a number cast into the rear cover 3871875 which I assume is just a casting # for that part.
There is also another number, H49, which is stamped into the diff which I hope identifies the gearing.
Can anyone confirm this and read it? Thanks
Mark
There is a number cast into the rear cover 3871875 which I assume is just a casting # for that part.
There is also another number, H49, which is stamped into the diff which I hope identifies the gearing.
Can anyone confirm this and read it? Thanks
Mark
Race Director
Joined: Apr 1999
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From: Beverly Hills/Pine Ridge Florida
It's September 26, 69, not August. 
AO code = 3.70 ratio. positraction...small block.
BTW, the "1" that precedes the AO is the shift when it was produced. The "W" stands for Warner Gear...where it was made.
Chuck
AO code = 3.70 ratio. positraction...small block.
BTW, the "1" that precedes the AO is the shift when it was produced. The "W" stands for Warner Gear...where it was made.
Chuck
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Joined: Aug 1999
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From: Connecticut, USA
There's also a chance they have been replaced over the past 35 years. Count the number of rotations of the input/axles to get a rough idea if they are 370's. What was your 60 mph rpm?
Gary
Gary
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Joined: Sep 2002
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From: Epping NH
Actually, I can count. My fingers just work faster than my brain (9 = September, duh).
Thanks for the help decoding this. I suspect that this unit has never been out of the car before and the 3.70 remains.
Thanks!!!
Mark
Thanks for the help decoding this. I suspect that this unit has never been out of the car before and the 3.70 remains.
Thanks!!!
Mark
