Mostly because I have a need for enough items to make the shipping from Rock Auto more advantages than buying local.................and I know about the going to h#$@ for not buying local argument............

But can you tell if a heater core is standard or HO without pulling it? 1974, non AC single cab, no emblem inside saying HO, basic controls. I have searched here but didn't find anything definite. I'm betting standard core. I've seen the threads on seals in the box.

Thanks in advance. Looking to minimize downtime of my toy.

 

"high output" was printed on the heater box in white letters on mine... you might be able to use a flashlight and look up under the dash...

 

No wording about output but it does have 3-J-19-B printed on it (this appears to be pad printed on the the exterior of the box, viewed while its still in place) and T 5 or S that was part of the mold when the housing was cast or laid up. Thanks again.

 

C6OZ-18476-B .. Heater Core with 8" core / Obsolete

1966/70 Falcon without A/C / 1966/72 Fairlane/Torino without A/C / 1971/72 Mustang/Cougar without A/C

1973/79 F100/350 & 1978/79 Bronco with High Output Heater.

 

Thanks for the part number for the core. Does the B printed in the number on the outside of my box correspond with the B in the part number for the HO core? The housing or heater box is still in the truck and I was hoping to figure out what core was there to minimize the time the truck was apart. Thanks

 

Part number will not be listed anywhere on the heater. Even if it was, you usually cannot go by it, because...

FoMoCo is in-famous for updating/replacing part numbers more often than women change their minds!

 

Just to follow up.

It's a standard 6x6 core.

Maybe the outward clues I have will help someone in the future, but based on my search here and Number's advice.........it's a crap shoot. Thanks again.