yes I think the oem seal is not available anywhere and it has 2 true lips to help seal the oil. the ones we find are 1 true lip and a small flap. the seals available have different springs rate, and I realize due to testing the strongest the spring the more it will last before dripping. 2 springs will compensate for the aftermarket seal not having the 2 true lips the oem had. I always use mobil 1 jet oil