GM-50298 installs both the left and right-side axle seals in the AF40-6 transaxle. It also installs the left-hand axle seal on the 2010 and beyond Cadillac SRX. The tool has a stepped OD that expands the seal lip and garter spring to avoid dislodging of the spring when the seal flange bottoms against the trans. It also has a smaller OD that serves as a pilot to assure the seals are aligned with the case and cover bores as they are driven into place. Even though the seals are flanged, there is concern that they may not be driven in squarely and completely, which is why this tool has a long pilot and is made of steel to prevent the seal from springing back.