I know, weird question huh? OK, here's the deal. I have a 2006 Trailblazer EXT/LT with the 4.2 engine....it's been solid for the entire 235,000 miles with not many issues at all. Since it has high miles, I frequently check the oil at least once every two weeks if not more and have the oil changed, typically every 5,000 miles or so...sometimes less sometimes a bit more. And, I am always checking my gauges. Anyway, a couple weeks ago, while just getting off the expressway and coming to a stop at the end of the ramp. As I accelerated, I heard a knocking and immediately let off the gas and checked gauges...they were fine until suddenly, oil pressure dropped to ZERO. I shut it off, shoved it in neutral and coasted into an auto parts parking lot. Got out and checked for leaks....NOTHING. Checked coolant thinking possible head gasket but no oil in coolant. Then I checked the oil....it didn't even register on the stick. Went in and bought 3 quarts and put them all in....still nothing. Put two more in and finally full. Waited a bit, started it up, oil pressure came right up but still heard knocking....pressure dropped to ZERO again and I shut 'er down. This car does not leak or burn oil and the head gasket didn't go so WHERE DID THE OIL GO? I thought and thought and talked to a couple mechanics and explained the situation and it seems like the common answer is....someone took your oil. WHAT??? I know, it's very weird especially considering I live 300 feet off the road in the woods and everybody loves us . After thinking about this for a while, I filed a vandalism claim with the insurance company but they denied it saying it was simply and engine fail (the claims adjuster said "we don't see there has been any tampering with the drain plug"....I said, "it's been "tampered" with every 5,000 miles so what the heck are you talking about") But....WHERE DID THE OIL GO? Here's another weird thing...a couple days later, the exact same thing happened to my daughters Nissan Sentra. Coincidence? I don't think so! Now, the day before this happened to the Trailblazer, I discovered some fiber like material, like wig material, about a foot long (black, gray and white) hanging out of the tailpipe. First thought an animal crawled in and I fried it but no animals like that around here. Don't know if this is related or not but thought I'd just throw it in for consideration. Anyway to cut this a bit shorter, I'm looking to appeal to the insurance company because I can't seem to come up with any other answers other than someone took the oil. So, does anybody out there have any other answers for me? Am I spinning my wheels trying to appeal? HELP!!!