I have checked and done everything to this truck and it is still smoking coming through the tail pipe and it's a grayish/blue color and smells like oil. I have changed valve covers and gasket and pcv valves. Comppression test was perfect at 185 on all cylinders. There's oil showing up in the galley of the throttle body. I installed an oil catch can and it's been on for a little over 3 weeks and it is bone dry. I have also had a leak down test done and it is good also. It didn't start smoking until 2 weeks after I switched to full synthetic mobil 1 and a mobil 1 oil filter. Any help would be gladly appreciated. The truck runs great except for the dang smoke .