It started yesterday when they oil pressure was running at 30 instead of closer to 45... so i checked and added oil hoping it would be fine. i have an oil leak, and it would either run high when it needed oil or run low if i needed oil. Today, it was running at 15 and then it even went to 0. it would especially go to 0 and stay there in reverse and after running a while would go close to there no matter what. but would raise up to about 15 while pushing on the gas. later when i started my truck to go home it was at 30, but by the time i was near home it was at 15 and i backed in so i could maybe look at it tomorrow. as soon as i put it in reverse it went to 0 and stayed there until i turned it off. any help would be greatly appreciated, matt not expecting positive feedback since a friend and i found the inside of a lifter in his oil pan after he experienced similar issues and he's currently in the process of replacing his cam, lifters, push rods, etc.