3DDesign Carbon Rear Diffuser for G29 BMW Z4 M40i

The 3DDesign Carbon Rear Diffuser for the G29 BMW Z4 M40i adds a bold, performance-inspired upgrade to the roadster’s rear end. Crafted from high-quality carbon fiber, it is lightweight yet durable, providing a sleek, race-ready appearance. Designed to integrate seamlessly with the factory M40i rear bumper, the diffuser features sculpted fins that enhance visual depth and give the Z4 a more aggressive, athletic stance. Precision-engineered for perfect fitment, it complements the exhaust setup and other 3DDesign aerodynamic components, elevating both style and dynamic presence for a complete OEM-plus look.

Gtechniq EXOv5 Coating

• This optional coating forms a durable, long-lasting bond that will not wash off or break down, providing reliable, extended protection for paintwork and other treated surfaces. It creates a strong protective barrier that helps shield against damaging environmental contaminants such as dirt, road grime, and pollutants, while also offering enhanced scratch resistance to maintain a clean, high-gloss finish over time. For those seeking maximum durability and performance, the coating can be applied in multiple layers to increase thickness, strengthen protection, and further extend the life of the surface.

Features

• Made from high-quality, lightweight carbon fiber for durability and strength
• Enhances the rear with a sporty, aggressive, and race-inspired appearance
• Sculpted fins add visual depth and dynamic character
• Precision-engineered for seamless OEM-plus fitment
• Compatible with factory exhaust or 3DDesign quad-tip setup
• Complements other 3DDesign aerodynamic components for a cohesive look

Applications

• BMW Z4 M40i: G29 (2019-present)

Notes

• Only compatible with M40i models
• Compatible with 3DDesign 4-tip exhaust as well and OEM exhaust

About 3DDesign

3DDesign is a Japan-based BMW specialist recognized for OEM-level fit, refined aesthetics, and real-world performance. Drawing on motorsport development, the brand engineers aerodynamic components, wheels, exhaust systems, suspension, and interior accessories using advanced CAD / CAM, CFD, and road / track testing. Its catalog emphasizes lightweight, high-quality materials — such as carbon fiber, forged aluminum, and titanium — paired with precise tolerances for seamless integration with factory systems. The result is a cohesive, OEM-plus driving experience that elevates both form and function across modern BMW platforms.