hello i know it has been on here tons of time but i have a blocked heator core the lower half that is i did the flush and no better i was woundering if ther is any way i can use a chemical to break up the lower block in the heator core becuse it is in the teens to nagitive with the wind chil thx bobby

 

You can buy radiator flushes. I'm sure these will help with the heater core. Just poor it into the radiator. Run the truck for a while to get it circulating. Then after a while drain the radiator and then flush the heater core. You can also try a higher pressure hose. If you used just a garden hose. Step it up and go to a low pressure car wash. If you dare go higher. It does have a chance to blow inside the truck, but its your choice if you choose to. I did it, it cleared it up perfectly and did not blow mine. Also do it both ways, and do it 10-20 times.