Why wouldnt you just drain the radiator and run water through it with the truck running and the heat on? Those plugs look like they're in there pretty good. I had one break in an old truck so i don't touch them unless i have to. Plus it's probably better to run some water in there than just drain it all and replace.

 

most motor have a block drain(s) it is the only way to do a complete flush and fill

Thanks for the pics

 

I agree. Also you don't need the heat on unless you have a valve on the heater core. Our trucks don't have this, at least not that I have seen.

 

I thought that's how you controlled how much heat you got. I was under the impression that as you turn the **** from hot to cold, the flow through the heater core is being increased.

 

Remove the upper radiator hose from the radiator , put a garden hose in the rad cap hole , start truck , when the thermostate opens it will pump out all the dirty water , just keep rad full with hose , after its clean drain & add coolant as needed ...Lew

 

The heat on our trucks is controlled by the air going through the core by the damper doors in the air box. The coolant flows through the coil at all times, no valves. I usually install a flushing "T" on the heater hose rather than deal with the drain plugs.
regards
rikard

 

I've only pulled these plugs if I needed to pull the motor or pull the heads just so I don't get coolant everywhere. Pulling those plugs to do a coolant change is like removing the cylinder heads to do a spark plug change. There are other ways to do it.

 

I would agree there are other ways to do it but flushing from the rad side will not get the particles sitting in the bottom of the block out, that method only get you clean water in the system. I do not do the block plug removal on every fluid change but it should be done at least once to get all the particles/ solids out and yes it will be messy.