One problem related to oil pump has been reported for the 2009 Chevrolet Silverado. The most recently reported issues are listed below.
The first incident occurred while driving the vehicle on the highway. The engine light came on and the dash readout gave a low oil pressure warning. The truck was towed to the dealer. They said it was a bad oil pressure sensor and replaced it at a cost of approximately $450. 00. Five months later the same problem happened again while driving on the freeway towing a horse trailer. I again had the vehicle towed into the dealer. They said the oil was low and did an oil change. The warning light was off when we got the truck back. The latest incident happened on 4/18/2015. The engine light came on again. I brought the truck to an auto parts store where they read the fault code. The code is p0521 - oil pressure sensor or oil low. I checked the oil it was nearly full but I added a little anyway. The light stayed on. I made an appointment at the dealer. The light went off the day before our appointment. I brought the vehicle to the dealer and now they are telling me that the truck probably needs an oil pump and a valve cover and it will cost approximately $1075. 00 to fix. I have done extensive research on this problem on the internet. There are hundreds of owner complaints on various websites documenting the same problem I am having. There appears to be a defect in the design of the oil system in these vehicles. My truck just went out of warranty in December 2014. They want me to pay for this repair even though I have already paid for repairs for the same problem while it was under warranty. This appears to be a serious product defect and gm should issue a recall.