I recently bought a complete set of Rally Wheels off of Ebay. All of the numbers match on all four of them. I was wondering if anyone knew how to decode the stampings on the back of the wheel?
Here is what mine read:

X A 03 13 85 991 JJ MW5 T CANADA

I thought maybe the production date was the 03/13/1985 but wasn't sure about the rest. Any help would be appreciated.

 

I would like to know the same thing.
Here is my list of numbers.
My Rims are 15 inch, which means they are from 1975+.
Guess #1 W 2 16 4, could mean February 16, 1974?
Guess #2 975, could mean September 1975?

OD 15x7 JJ
Made in Canada B
W 2 16 4
M5 7 975

 

Here is what I know.


The 975 is the outer ring number(bent a certain way)


M57
M=Motor wheel
5= Windsor? Canada Plant
7= 1977


This is a guess on these. ???
W=Windsor
2= February
16= day
4= ?


Mike

 

X A 03 13 85 991 JJ MW5 T CANADA

991 outer ring number(bent a certain way)


M=Motor Wheel
W?= Windsor Canada Plant
5= 1975 or 1985 Need to see rim.


03= March
13= 13th Day
85= 1985?
XA= Wheel Code


Really need to see rim.


Mike

 

My guess for my rims is that the “W 2 16 4” numbers are a date code.

The reason I chooses these numbers is because you have to change the casting value every Day or Week of production.
The date numbers are either Cast into the Rim (very expensive) or Stamped onto the rim after it’s made (much cheaper to implement).
The W numbers are not straight. Each set of digits is rotated at a different angle, which to me indicates these values changed frequently.
All of the other stamps have the numbers and letters spaced consistently.

Since Oldsmobile started selling 15 inch Rally rims with the 1975 Oldsmobile’s, Ill guess they started making the rims in 1974 for the 1975 product line.

 

1974 was the first time the SSII 15 inch was offered along with the 14 inch SSII.


N66 was SSII 14inch
N67 was SSIII 14inch
N71 was SSII 15inch
N72 was SSIII 15inch


Mike

 

Here is a picture of mine as requested. I hope this is what you were needing.