I try not to ask them any questions, as this particular AZ has workers with the intelligence level of the average carnival ride operator. two out of the three times I went to get the oil, I had to go behind their counter to find the oil myself because they kept bringing me Mobil 5000 and telling me Mobil 1 doesnt make a High Mileage Synthetic....even after I showed them a quart of HM 10w40