I have a 2011 Gmc crew Sierra 1500 with the 6.2 in it. It has 75,000 miles. I recently installed a procharger. When I floor it I get an oil leak which looks to be coming from the rear main seal. The next day there will be no oil leak. I can drive normally for a week with no oil leak. When I floor it, it will make a puddle under my truck and will be slowly dripping for a little while. Any one know what is happening?