The MMX Performance G8X M2 / M3 / M4 Ultimate Track Differential Kit brings together the full MMX rear differential package for the BMW G87 M2, G80 / G81 M3, and G82 / G83 M4. It combines the four-point differential mounting system with the High-Capacity Baffled Differential Sump and the Rear Differential Output Shaft Heat Shield Set, covering differential mounting, driveline geometry, oil capacity and cooling, and CV boot heat protection in one kit. It fits both RWD and xDrive models and can be installed at the factory differential height or in a +10mm raised position.

The mounting system is the same as the 4-Point Differential Lift Kit. The MMX Front Differential Lift Mount / Cradle (MMR55-1604) replaces the factory front differential mount, the MMX Dual Differential Mount (MMR55-1606) adds support at the secondary bush location that goes unused in the factory setup, and two MMX Rear Differential Raised Poly Bushes (MMR55-1605) complete the four mounting points. At OEM height, the system reduces differential movement under load. In the +10mm position, it raises the differential by 10mm. Lowering a G8X changes the operating angle of the rear driveshafts. Raising the differential by 10mm corrects that geometry, reducing heat and premature wear on the CV joints and axle shafts.

The MMX High-Capacity Baffled Differential Sump (MMR55-1600) replaces the factory differential sump using the factory mounting points. Machined from 6061-T6 billet aluminum, it increases differential oil capacity by up to 2 liters (2.1 quarts). An internal windage tray maintains gear and pinion lubrication while reducing component drag, and internal and external cooling fins increase the surface area available for heat dissipation. An additional -8AN port, with an M22 to -8AN adapter included, allows an external differential cooler to be connected. The Dual Differential Mount attaches directly to the sump with no additional hardware.

The MMX Rear Differential Output Shaft Heat Shield Set (MMR55-1607) places a pair of aluminum shields between the exhaust and the rear output shaft CV boots. Under sustained track use, radiant exhaust heat can crack the boots, allowing grease to escape and leading to CV joint wear, particularly on cars running an aftermarket exhaust. Each shield has a polished heat-reflective face toward the exhaust and a black anodized outer face, and the set works with both factory and aftermarket exhaust systems.

MMX G8X Differential Kit Comparison

• 3-Point: Front Differential Lift Mount / Cradle and one Rear Differential Raised Poly Bush.
• 4-Point: Adds the Dual Differential Mount and a second Rear Differential Raised Poly Bush.
• Complete: Adds the High-Capacity Baffled Differential Sump and the Output Shaft Heat Shield Set to the 4-Point system.

Product Details

• Complete package: four-point differential mounting system, high-capacity differential sump, and output shaft heat shield set
• Front cradle, dual differential mount, and two raised polyurethane rear differential bushes
• Installs at OEM differential height or +10mm raised
• +10mm raised position corrects driveshaft geometry on lowered vehicles
• Up to 2 liters (2.1 quarts) of additional differential oil capacity
• Internal windage tray with internal and external cooling fins
• Additional -8AN port with M22 to -8AN adapter for an external differential cooler
• Heat shields deflect exhaust heat away from the rear output shaft CV boots
• Cradle, dual mount, and sump machined from 6061-T6 billet aluminum
• Direct fit with no modification required
• Fits RWD and xDrive models
• SKU: MMR55-0003

What’s in the Box

• 1 x MMX Front Differential Lift Mount / Cradle (MMR55-1604), replaces the factory front differential mount
• 1 x MMX Dual Differential Mount (MMR55-1606), adds support at the factory secondary bush location, mounting hardware included
• 2 x MMX Rear Differential Raised Poly Bush (MMR55-1605), one replaces the factory rear differential mounting bush and one fits the dual differential mount
• 1 x MMX High-Capacity Baffled Differential Sump (MMR55-1600), replaces the factory differential sump, supplied with the windage tray, magnetic drain plug and seal, fill plug and seal, M22 to -8AN adapter, and mounting hardware
• 1 x MMX Rear Differential Output Shaft Heat Shield Set (MMR55-1607), pair of shields for the rear output shaft CV boots, mounting hardware included

Notes

• Differential height is selected during installation. The front cradle and both rear bushes must be set to the same position, OEM height or +10mm raised.