Maximum Motorsports IRS Aluminum Differential Bushings

Maximum Motorsports IRS Aluminum Differential Bushings (Adjustable pinion angle, 3-bushing set)



Aluminum Differential Bushing Kit:

• The MM Aluminum Differential Bushing Kit replaces all three stock rubber bushing sets.


• The MM Aluminum bushings allow the pinion angle to be raised by over 4 degrees. This means that the pinion angle can be adjusted to minimize driveline vibrations.


• The MM front differential bushings are comprised of specially machined spherical washer sets. This allows compensation for the changed angle of the differential housing. If these aluminum bushings did not have this feature, the stress on the differential mounting ears and the IRS subframe would be increased.


• Unique to the MM kit is the rear bushing. Overlooked by others, this bushing contributes just as much to reducing wheel hop as the front differential bushings.


• The aluminum bushings are surprisingly unobtrusive. The change in NVH is minimal. There is a slight increase in the noise level from the ring and pinion gears. Changes in vibration and harshness levels are virtually unnoticeable, with the exception of driveline vibrations being reduced due to the corrected pinion angle.

Reduce wheel hop by installing stiffer differential mounting bushings. MM offers two types of differential bushings, urethane and aluminum. The urethane bushings are much stiffer than the original rubber, yet are still compliant enough to dampen NVH (Noise, Vibration and Harshness). The aluminum bushings allow no deflection at all, and therefore do more to reduce wheel hop. The aluminum bushings are designed to provide adjustment of the pinion angle. Properly setting the pinion angle helps keep driveline vibrations to a minimum.



Unlike many others who offer only the front differential bushings, Maximum Motorsports took the time and effort to actually analyze the IRS system. The MM Engineering Team realized that all of the differential bushings must be replaced as a set. The complete set includes the two front bushings and the essential single rear bushing. If only the front bushings are replaced, and the original rubber rear bushing is left in place, a mismatch will be created in the stiffness of the bushing materials. The more rigid front bushings will deflect less, while the remaining rubber rear bushing will still deflect as much as ever. This in turn will increase the stress on the aluminum front mounting ears of the differential housing. The increased stress can lead to fatigue and stress cracking of the aluminum differential housing. Wheel hop will still be prevalent because the rubber rear bushing will deflect and allow the differential to flop around.