Question for the numbers guru's

[Geetex]

Where is the date code on a 489 differential case and is it a regular calendar date or a 10,000 day calendar date or something else?

 

[Mopars & Missiles]

 

[Geetex]

Thank you M&M.

 

[Mopars & Missiles]

Thank you M&M.

'70 model, others may or may not be the same.

 

[69Coronetrt]

Where is the date code on a 489 differential case and is it a regular calendar date or a 10,000 day calendar date or something else?

Mine showed a casting date in week/year (29/8) format. There are a couple of date codes on the ring gear

 

[69Coronetrt]

'70 model, others may or may not be the same.

Mine was similar (Oct 29 1968)

 

[Mopars & Missiles]

View attachment 939892

Yes, mine was 9-12-69 for a '70 Challenger. SPD on the car was 9-17-69.