My '06 BMW will have its CPO warranty expire at the end of the year. I had my 60k service due so decided to take the car to an independent shop to find out if there were any issues. They showed me there was a small leak at the rear main crankshaft seal. I don't know much about cars but I told the dealership when i brought my car in that I had an oil leak. They checked it out and called me next day to say that there is a leak from the power steering hose. Should I tell them the leak is from the crankshaft? Isn't that something they should have found themselves. I dont know if they will ask me how I know this is where the leak is from. any advice?