2009 non-turbo Clubman. Brought it home on a U-Haul auto trailer yesterday after purchasing it. Loading it the front stop when under the bumper. This is only the with of the ramp on each side in the front of the trailer. There was a small 4 in puddle of oil on the trailer in front of the passenger wheel that I noticed after unloading the car. There is no oil on the ground today. Oil level has not dropped since then. What might I have hit in that spot? The stop is 6 inches or less high. I thought I only hit the lower cover on the bumper. I did not see anything but asking the experts as I am new to this car.