Rear diff tag
Post Fiend
Joined: Nov 2007
Posts: 9,549
Likes: 14
From: Payson, AZ
I used my own diff tag in this example.
S409B
3L73 102 8C11
The break down of these codes:
S409B:
S = Sterling Differential
409 = Print Number (Model Number)
B = Revision Identifier (Change in Design)
3L73:
3L73 = 3.73 Ratio
L = Limited Slip
Absence of L = Open Differential.
102 denotes the ring gear size of 10.25 inches. 105 would be a 10.5 inch ring gear.
8C11 is the build date.
8 = year of manufacture. In this case it means 1998.
C = month of manufacture. A= January, L= December so C= March
11 = day of manufacture. So my differential was manufactured on March 11, 1998
The tag numbers you posted are not complete.
There should be a 3 in front of the L73 and a 2 or 5 after 10
So you have a Limied Slip 3.73:1 ratio and either a 10.5 or 10.25 ring gear.
Build date is Oct 30, 1999.
S409B
3L73 102 8C11
The break down of these codes:
S409B:
S = Sterling Differential
409 = Print Number (Model Number)
B = Revision Identifier (Change in Design)
3L73:
3L73 = 3.73 Ratio
L = Limited Slip
Absence of L = Open Differential.
102 denotes the ring gear size of 10.25 inches. 105 would be a 10.5 inch ring gear.
8C11 is the build date.
8 = year of manufacture. In this case it means 1998.
C = month of manufacture. A= January, L= December so C= March
11 = day of manufacture. So my differential was manufactured on March 11, 1998
The tag numbers you posted are not complete.
There should be a 3 in front of the L73 and a 2 or 5 after 10
So you have a Limied Slip 3.73:1 ratio and either a 10.5 or 10.25 ring gear.
Build date is Oct 30, 1999.
Post Fiend
Joined: Nov 2007
Posts: 9,549
Likes: 14
From: Payson, AZ
Don't know the date when they went to the 10.5. Probably some time in 1999.
Manu date on diff is March 11, 1998. Manu date of truck is March 1998.
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