I’m looking to verify a 12 bolt casting date. Is L198 December 19th 1968? If so, what would be the expected assembly date for a car with an L198 axial?

Does Chevelles.com have a casting date decode page?

Thanks,
Mike

Originally posted by mike69ss:
I’m looking to verify a 12 bolt casting date. Is L198 December 19th 1968? If so, what would be the expected assembly date for a car with an L198 axial?

Does Chevelles.com have a casting date decode page?

Thanks,
Mike No, that would be November 19, 1968. Remember, the monthly letter codes skip 'I' because it looks like a number one:

A=January
B=February
C=March
D=April
E=May
F=June
G=July
H=August
J=September
K=October
L=November
M=December

Typically the parts were used within about 2 months of a casting date but they could have been used within a month of casting or sometimes the date is 6 months or more off but those instances are uncommon.

How could an axle cast in Nov. '68 have been installed in a car with a build date of say May 1969? Two likely scenarios are possible, I'm sure there are more:

1. the axle got misplaced in inventory for a time
2. the axle was found to be faulty during the build of the car, when this happens they don't stop the assembly line, they mark it as faulty and send it down the line. At the end of the line the axle is replaced. The area doing the parts swap sometimes had inventory that was a little older since they go through inventory less quickly. But more specific to your question, if the axle was cast mid-Nov. 1968 I would venture a guess the car was built about mid-Jan. 1969 or thereabouts.

Sometimes a larger than average disparity is seen on engine casting dates and car build dates in cars with high performance engines since the engines were often built in batches but not used out of inventory at the same speed as bread and butter engines. Whether the same might be true for axles with more rare options (like a posi with 4.11 gears) I cannot say but it would make sense.

My car was built 12B, and the rear is K138.

In other words, the rear was cast November 13 1968 and the assmbly time was December 2nd week.

Rich, I have been researching and found that I= Sept. I think that his rear is a December casting. Respectively of course.

You may be right. I may have been thinking about alternator and starter dates:

http://heartland.chevelles.net/RCstorage/starternums.jpg

http://heartland.chevelles.net/RCstorage/altnums.jpg

I don't recall seeing a casting date with an "I" and coupled with the above information I've always believed casting dates worked the same way. But then Muncie date codes and POP date codes work in different ways altogether so perhaps casting dates do to. But I'd swear I've seen "M" casting dates too.....

Can anyone else shed any more light?

I believe the axle is original and the build date for the car is the second week of Jan 1969. So Novemeber would give the two month leadtime, but as has been pointed out one month between cast and build also works.

So, I'm still not sure what month "L" stands for.

Thank you for the replies

Stamped dates don't use I, so M would be December for starters, alternators, etc (Delco-Remy products).

Cast dates (blocks, heads, rear center sections, etc.) do use I, so L would be December. Your rear axle would be cast in December. What is the stamped assembly date on the axle tube?

I have seen some rear ends with a delay of up to a month or two from casting date to rear end assembly date. Then the rear is shipped to the vehicle assembly plant where there can be additional delay until it is assembled in the vehicle, but this delay is usually only a couple of weeks or so.

I'll look for my notes for the build date. That's where I recorded the stamping. After I painted the rear I don't know If I can still read the stamping