I took my car into the Canadian Tire pit stop to have the oil and oil filter changed. I had already changed the air and fuel filter myself at home. I left the car and went into the store to shop. When I returned to get the car, I had been charged for a new air and fuel filter. I was furious, and told them to get my parts from wherever they had put them, and put them back on the car. I told them they were criminals, but did not receive an apology. I was then told by a friend that the emplyees of the oil change dept. get a commission on all parts they can sell. I don't know if this is true, but will never get my oil changed there again.