I need some help on this one. I just bought this truck used back in February and i have put about 6000 on the truck since then and have a totally of about 103K on the truck now. Its the 5.3 1500 z71. I got my oil changed about 3 weeks ago and the low oil warning came on and its the third time its done it. first time came on about a month ago around Easter and I just added oil to it to get it back to the level it should be at since I did not need an oil change quite yet, then like I said about 3 weeks ago it came on again and decided to go ahead and change my oil and see if that helped, I put Pennzoil high mileage in when I changed it. Well yesterday it came on once again. Each time it has come on the truck was about two quarts low (hardly any on the bottom of the dip stick). I have not a clue why it is doing this, my truck doesn't smoke or leak oil from the bottom? So how possibly is it getting low if I am not burning oil nor is it leaking out the bottom??? Thanks for the help guys.