Robert Wilkins

For those to short to look over the top of your radiator down to the bottom with a flashlight don’t dispair. Those who are to fat to slide under the front grille and lower valance don’t despair. For those who don’t know what a small plastic wing thumb screw feels like Or a petcock your In trouble!!!! Seriously every GM truck I’ve owned (every 4-5 years gone) has had a drain which is always only thumb tight. Perhaps it’s because I order trailer package with HD radiator I’m not sure the reason but if you slide your LEFT hand up your babies skirt from the passenger side while on your back locate the radiator corner and hose by feel you can’t really see them unless you bend your babies underbelly skirt hard which might break it. It opens with a little force not much and no need to remove it all the way itll drain fine. While this probably won’t remove all radiator fluid it removes a lot now close the valve This is the point u open your cap if lucky you had enough vacuum to empty your overflow reservoir add 1 gallon 50/50 mix close cap run till warm and cycle or run heater on high to get the old stuff out of heater core and shut motor off (only run it until the thermostat opens under 200’ always watch temperature while doing this never let your engine over heat this step usually only takes 4-7 minutes tops. While you let it cool it should draw all fluid out of reservoir since you replaced the cap before starting engine. You can also manually drain the reservoir but I prefer siphon or pump method if it didn’t draw back in by vacuum as plastic breaks at the worst time always. AFTER engine cools Now remove the radiator cap yet again and add your new coolant 50/50 is fine I prefer 65% coolant and 35% distilled water. That’s me from my Dad he said probably doesn’t make a difference but if NASA uses it I’m using it. When full replace the cap and add fluid to reservoir and then drive for 15-20 minutes to cycle and burp the system then add if necessary but I would check it at least to more times just Incase you had air pockets or whatever. In closing always watch your gauges now your normals so when something happens you’ll know what your normals are. I taught this to my children and they are now guage watchers. I like GM as most of their gauges on trucks are clocked to straight up is in normal state anything other than up is something to look at even gas if it left of up stop and fill.