'05 Chevy TB EXT
NOPE __ TAIN'T BLOWBY.
Can you provide a part number for the PC Valve you say you can change?the PCV can cause increased crank case oil pressure, which gets relieved through the spark plug tube seals and valve cover gasket. whichever gives first. either is better than the head gasket. any time you've got missing oil it could be something less than great. pint every three thousand is enough to start investigate for sure. i like to change my 4.2 L6s at three when im running dinosaur oil and getting it done somewhere.
point is you may as well have that PCV changed on while they in there. should have almost no oil usage and minimal leakage afterwards. as long as they are competent or experienced with the atlas motors. sounds like wrench #1 just didn't know what they were looking at.