Performance Air Filter for BMW X3/X4/X5/X6 Diesel

Precision High-Flow Induction for the BMW N57 Diesel Powerplant

Who It’s For: Engineered for BMW X-Series owners running the N57 inline-six diesel engine who want to maximize volumetric efficiency without compromising engine safety.

The Symptom: The factory intake system on the N57D30 engine is designed around a thick, disposable paper element. While it meets basic filtration standards, it creates a significant pressure drop across the filter surface as it collects soot and debris. In a high-torque SAV (Sports Activity Vehicle) like the X5 or X6, this restriction forces the turbochargers to work harder to pull air, resulting in increased intake temperatures and a noticeable lag in throttle response when merging or towing.

The Engineering Fix: This BMC performance filter utilizes a multi-layered cotton gauze media, soaked in low-viscosity oil to create a "tacky" mesh. Unlike paper filters that block airflow to stop dirt, this system uses "depth loading" to capture particles as small as 7 microns while maintaining a much higher CFM (Cubic Feet per Minute) rating. By reducing the resistance in the intake tract, your N57 can achieve target boost levels faster, smoothing out the power delivery across the entire RPM range.

Why Mechanics Choose This Kit

• Enhanced Volumetric Efficiency: By allowing the N57 turbos to breathe easier, you reduce the pumping losses associated with the factory 10-micron paper filters.
• Full Moulding Construction: BMC uses a unique "Full Moulding" process which creates the entire filter from a single soft rubber compound. This ensures a perfect airtight seal in the OEM airbox, preventing "dirty air" bypass.
• Lifetime Durability: This isn’t a disposable part. The epoxy-coated alloy mesh protects the cotton media from engine backfires and moisture, and the entire unit can be washed and re-oiled for a lifetime of service.

Technical Specifications

Compatibility & OEM Reference

Fits the Following Vehicles:

• BMW X 3 (F25) 30 DX (258 HP) 10/11 > 17
• BMW X 3 (F25) 30 DX (277 HP) 16 >
• BMW X 3 (F25) 35 DX (313 HP) 11 > 17
• BMW X 4 (F26) 30 DX (258 HP) 14 >
• BMW X 4 (F26) 30 DX (277 HP) 14 > 18
• BMW X 4 (F26) 35 DX (313 HP) 14 >
• BMW X 5 (E70) M 50 D (381 HP) 12 >
• BMW X 5 (F15, F85) 30 D (258 HP) 13 >
• BMW X 5 (F15, F85) 30 D (286 HP) 13 >
• BMW X 5 (F15, F85) 40 D (313 HP) 13 >
• BMW X 5 (F15, F85) M 50 D (381 HP) 13 >
• BMW X 6 (E71, E72) M 50 DX (381 HP) 12 >
• BMW X 6 (F16, F86) 30 D (258 HP) 14 >
• BMW X 6 (F16, F86) 40 D (313 HP) 14 >
• BMW X 6 (F16, F86) M 50 D (381 HP) 14 >

Interchange Part Numbers:

FB821/04, B: 149, A: 357

The Performance Promise

Buy with confidence. This BMC air filter is a direct drop-in replacement for your factory airbox, maintaining your BMW’s stock appearance while providing professional-grade filtration and airflow. Backed by real automotive experts and fast shipping.