Heater core date code?

**R68GTO** · #1 11-04-2020, 12:43 AM

Do big block heater cores have a date code? If so, where would I find it?

**X66 714** · #2 11-04-2020, 12:49 AM

I would think all Harrison heater cores have a date code. I've seen it on one of the tanks...Joe

**Big Block Bill** · #3 11-04-2020, 12:55 AM

All of the Original GM Heater cores I have seen have been stamped on one of the side "Tanks" with the month (1 Digit) and the year (2 Digits). My LS-6 was a 03D Arlington built and it was stamped 3 70 A good radiator shop can re-core a heater core like a radiator. Bill

**68camaroz28** · #4 11-04-2020, 01:09 AM

Here is an example of the date code on Harrison heater cores dated 67L.
https://www.camaros.net/threads/time...5#post-1690789

**WorkinProgress** · #5 11-04-2020, 01:14 AM

Harrison cores are what GM used. The end tank opposite the necks, will say Harrison and will have a date code. It will be the last two digits for the year, followed by a letter. The letter represents the month.

- Warren

**R68GTO** · #6 11-04-2020, 01:54 AM

Thanks guys. I'm assuming mine is original but will be nice to document the date code.