I'm doing some work for an extended warranty insurance company. I looked at a series of 11 engine failures over a two year period. These cars were lease cars that were used by sales people that put on a lot of miles in a short time. The drivers were very good at getting the oil changed sometimes at dealers, shops and quickie oil change places. Each of these cars had a dip stick failure. The stopper on the dip stick slipped up the dip stick causing the dip stick to fall lower into the engine crankcase. Evidently when the oil was changed the level was set at the same mark on the dip stick that was now lower in the pan and this led to stress on the lubrication system, being in some cases 50% low on oil. I wonder if we all verified the accuracy of our dip stick how many would not be giving a correct reading?