Bolt Saver Kit for BMW X3M and X4M rear differential bushing mount bolt.
This kit works with your OEM bushing. You do not need to press out the OEM bushing and you do not need to press in the new Bolt Saver. You must remove the aluminum OEM insert as it has too much play and makes the bolt wobble. The Bolt Saver kit includes a much thicker and much stronger replacement insert sleeve that is toleranced to remove excess movement and stabilize the mount bolt. The Bolt Saver Doughnut adds significant support in compression strength that supports both the bolt and prolongs the life of the OEM bushing. The Bolt Saver is an excellent alternative for those who want the OEM quietness combined with the compressive strength of Poly.