Radiator compatibility through the years

[79gmc15]

I am in the market for a radiator, looking at c-list and junk yards. What years can I look for that will work? I do have an automatic trans.  I believe my current radiator is a 3 core. My truck is a AC truck.

Thanks, Matt

[Captkaos]

1973-80 or 1981-87(91).

[79gmc15]

Thanks

[ron350]

 I just went through replacing the radiator in my 75 C10 and it was not fun finding a used brass/copper radiator.
If I had it to do over I would just go to Auto Zone and buy a new plastic tank radiator and forget about it.

These trucks also used more than one radiator core width so you have to watch that. I ran across 26” and 28” core width radiators in trucks at the junk yard.