so I have a 81 d150 all stock and it runs very well. I replaced my heater core when I first got it due to it steaming in the cab. I put on the 47.99 special from autozone with a lifetime warranty and it was fine up until about 2 months ago and it begin leaking out of the passenger side floor vent. it would only leak as it started to heat up and then it would not leak anymore. so I finally warrantied it and put in the new on e and it started leaking immediately. so I guess my question is, is it the cheap a$$ parts or do I have a problem possibly somewhere else is my cooling system? any help would be appreciated.

I would conclude Auto Zone has a batch of poorly manufactured off shore junk with heater core part numbers stamped on the box.

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Did you look at the cores to make sure they mounted properly and had nothing rubbing on them or poking holes in them?

_________________
Official Cookie and Mater Tormentor.