afm

I have a 2013 Sierra 1500 with the 5.3 Active Fuel Management system. I'm replacing the active lifters on cylinders 4 & 6 (for now) and bought ACDelco parts which I got from Rock Auto. The box that the lifters came in list the GM equivalent part number along with the ACDelco part number, which...

Dealer says use oil life, so i've been going by oil life. Truck has 83,000 km. At 30% oil life and 9500 km since last oil change, oil level was down (caught me by surprise being a newer vehicle, I don't check oil as often as I should and now I will) at tip of dipstick. Added a litre and still...