1997 Blazer here. Due to intermittant overheat problems and 3 shops not able to address the problem, I broke down and took to a dealer and they flushed the heater core. I don't have an overheat problem anymore, but I do have fogged windows with an oily type substance, which I presume is antifreeze. Could this be residue from the heater core flush causing this or am I doomed to replace the core?

Thanks!

 

Heater core flush opened up a leak. Time to tear the dash apart!

 

Taking the dash out is really not all that difficult....takes time and memory as to where all the screws came from though.

You could bypass the the heater core if you do not need heat this winter...

Heater core is cheap and easy to replace once the dash is out.