MMX Performance MINI F54 F55 F56 Rear Underbody Chassis Brace

The MMX Performance F-Series MINI Rear Underbody Chassis Brace replaces the heavy, aesthetically dated steel OE rear brace with a precision-machined billet aluminum upgrade. Engineered to deliver added chassis stiffness, improved dynamic performance, and meaningful exhaust clearance, without compromising ride quality or introducing any additional NVH into the cabin, it's the kind of detail-level upgrade that separates a finished MINI from a stock one.

The F-Series MINI uses three underbody braces to tie the chassis together: a front, a centre, and a rear. While the OE units are functional, they're overweight, visually crude, and (critically for any owner running a larger-diameter aftermarket exhaust system) give insufficient clearance under the centre tunnel. Many owners simply remove the OE braces to gain that clearance, sacrificing chassis stiffness in the process. The MMX braces solve both problems at once: clearance and rigidity, in one upgrade.

Each brace is machined from billet T-6061 aircraft-grade aluminum, then carefully profiled to remove a considerable amount of unnecessary material while preserving rigidity and ultimate strength. The result is a brace that's significantly lighter than the steel OE unit while matching or exceeding its torsional contribution to the chassis. The improvement in dynamic performance comes without any sacrifice in ride quality, and without introducing any additional noise, vibration, or harshness into the cabin, exactly the trade-off serious drivers want.

Finished in a deep gloss black anodized coating, the brace adds a finished, performance-grade appearance to the MINI's underside. Each brace is supplied complete with new installation hardware, uses existing body mounting points (no drilling or trim removal required), and is fully reversible. Available individually or as a complete three-piece set with the matching front and centre braces.

Product Details

• Direct OE replacement rear underbody chassis brace for F-Series MINI
• Machined from billet T-6061 aircraft-grade aluminum
• Provides additional exhaust clearance for larger-diameter aftermarket systems
• Gloss black anodized finish
• New installation hardware included
• SKU: MMR13-1401-R

What's Included

• One (1) MMX billet rear underbody chassis brace
• New installation hardware

Vehicle Applications

• MINI Cooper S / JCW (F55 / F56 / F57)
• MINI Clubman (F54)

Notes

• Rear brace only: front and centre braces are sold separately, or available as a complete three-piece set
• Includes a 1-year manufacturer warranty against defects in materials and workmanship
• Designed and tested in the United Kingdom