Aluminum heads...

I must be on the wrong thread because last time I checked, a Duramax was a Turbo Diesel Chevy/GM which is both diesel and turbo but not a powerjoke....have your rad flow tested and if its slowing down(clogged) then buy a new one. You dont really want to blow a tank off the core next time you are working your truck, by the time you realize it happened, its too late for the engine. It doesnt take very long ie 60 seconds at 40 psi boost to melt all the pistons with a load and no coolant. Consider it cheap insurance!