Thexton 356 Cooling System Backflush Tool - Universal Radiator Flush Kit for Cars & Trucks - Perfect for DIY Auto Maintenance & Engine Cooling System Cleaning

I have a 1998 GMC Jimmy and the heat had just stopped working on one of the first cold days of the season. I did a little checking and the water line going into the heater core was hot the one coming out was only warm. So, from that I knew that there was some blockage to the heater core. I did not want to tear the dash apart to put in a new heater core, so I decided to reverse flush it to see if that would help. I got some clear 5/8 and 3/4 inch clear hose, hooked it to the heater core so I could watch it flush. Some junk came out on the first flush, so I switched to the other input side and flushed it again. I went back and forth several times until the water was perfectly clear. I flushed into a bucket so I could see what was coming out. It worked and it is much hotter than it ever was before. I also changed the antifreeze. Saved big bucks on heater core replacement.