I started my truck to let it chill of before taking kids to swim practice and when I came out the their was over a gallon of oil on the driveway. It was coming out the top of high pressure oil pump around the sensor. I guess the oring let go after 300,000+ miles. I have never heard of a leak here. I checked everywhere starting from the bottom starting with the oil cooler. But as soon as I opened the good it was obvious were it was coming from.