Launch a G8X M car hard and the rear differential rocks in its soft rubber mounts. You feel it as a clunk and a delay between your right foot and the rear tires. The MMX Performance Rear Differential Bushing Insert Kit fills the voids in those OEM bushings, tightening the connection without the harshness of solid mounts.
The factory rubber stays, so it still drives like a refined M car on the street.
How the G8X Differential Bushing Inserts Work
Five CNC-machined 6061-T6 billet inserts slot into the existing rubber bushings, four at the front and one at the factory single rear mount. They limit differential movement under launches and quick torque changes while keeping most of the OEM vibration isolation. It is fully reversible. Going to a dual rear mount later? Add the MMX dual rear mount insert (MMR55-1619).
What's Included
- 4 x front differential bushing inserts
- 1 x rear differential bushing insert
Key Features
- Five-piece CNC-machined 6061-T6 billet aluminum kit
- Fills voids in the OEM rubber bushings
- Reduces differential movement during launches and torque changes
- Retains factory bushings for low NVH
- Fully reversible installation
- Part number: MMR55-1618
Vehicle Fitment
Fits the following models with the factory single rear differential mount, RWD and xDrive:
- BMW G80 M3 Sedan (2021-2026)
- BMW G81 M3 Touring (2023-2026, not sold in the US)
- BMW G82 M4 Coupe (2021-2026)
- BMW G83 M4 Convertible (2022-2026)
- BMW G87 M2 (2023-2026)
Installation Notes
Professional installation is recommended. The differential must be supported while the mounts are loosened.
- Support the rear differential and loosen the mount hardware.
- Insert the four front and one rear billet inserts into the OEM bushings.
- Lower the differential back into position.
- Torque all hardware to BMW specification.
