Something to consider is that the oil and coolant tests aren't definitive because of the way the head gasket can blow. But if you have white smoke and didn't before, and you have bubbles (exhaust) in your coolant overflow then yah it sucks to say but if it walks like a duck............
Also it seems coincidental how this problem is coinciding with your radiator replacement...........did the truck overheat when the radiator failed? If so then that is probably bad news.
Also it seems coincidental how this problem is coinciding with your radiator replacement...........did the truck overheat when the radiator failed? If so then that is probably bad news.