Ok so here's my problem.. I got the truck about a year ago and had no heat in the truck.. I eventually had some time and changed the heatercore. That did not fix my issue..so I drove the truck like that.. recently I've noticed my truck exhaust came disconnected.. week later the truck is over heating..so I parked the truck and changed the upper and lower rad hose thermostat water pump and clutch fan.. truck is still over heating.. open rad cap once it gets hot it just flows right out the radiator... pleaseeeee help.. I can't just keep dumping money in this thing.. it's going too be getting cold here soon and would like too fix the heat and overheating issues

 

Check the heater core hoses. Either they collapse or there is a clog. To do a quick check connect them together and if it doesn't overheat there is a clog somewhere from firewall to under the dash.

 

I have changed the heater core hoses when I replaced the heater core.. I even took off the one side of the hose and cranked the truck too make sure water pump is working

 

The lack of heat heat may be the blend door issue.
https://heatertreater.net/

What temp t stat did you put in? Also you should drill a small hole in the body, It will allow the air to get out. Read post #14...
https://dodgeforum.com/forum/2nd-gen...p-bleed-2.html

 

Maybe the T-stat like Hey you said or a clogged radiator. Assuming all the parts you mentioned you replaced are in working order. But parts can be bad out of the box. Or again like Hey you mentioned you have air in the system.

 

I have changed all blend doors before the truck had overheating issues

 

If the third gens are anything like the 2nd gens, the heater core is the highest point in the cooling system.... so, it traps air rather nicely. heater core isn't very efficient that way. Might try backflushing the heater core, just try and keep as much water in it as possible when you reconnect the hoses. See if that helps.

Overheating is probably unrelated to the no heat though.....

 

How exactly do I do the backflush? I had the truck running for about 20 mins with the rad cap off.. once it goes a tiny bit past normal it just starts flowing right out of the rad cap.. I just don't understand..

 

Disconnect both heater hoses. I just used my garden hose to flow water thru the heater core in the opposite direction of normal flow. Keep the ends of the hoses up higher than the heater core, and the water will stay in there. Use clamps, vice-grips, or whatever ya got to pinch off the hoses, so you lose as little as possible when you hook them back up.