BMW F97/F98 X3M/X4M (LCI) Diffusers
5 products
Every X3M diffuser on this page is made for the X3M alone, and the X4M, with its differently shaped rear bumper, gets its own. For the facelifted X3M, choose our 3-piece diffuser with rear corner splitters or an SQ-style pre-preg design. The X4M LCI takes an SQ-style diffuser, with or without a built-in brake light.
Our 3-piece is also the one to pick for a pre-LCI X3M. Not sure which bumper you have? Text a photo of the rear to 609-525-4865.
BMW F97/F98 X3M/X4M (LCI) Diffusers buying guide
X3M diffuser choices for the LCI
Our 3-piece X3M diffuser is a Unit 17 design, developed from 3D scans of the car. The kit pairs a center diffuser with rear corner splitters, in carbon fiber with a gloss, UV-resistant clear coat. Its pre-drilled holes line up with the factory screw locations, and the listing says no trimming or cutting is needed. It fits the X3 M before and after the facelift, but not the X4 M. If its listing shows Coming soon, ask us about timing before you order.
The SOOQOO 3-piece is pre-preg dry carbon with three integrated fins along its lower edge. It uses the factory mounting points and arrives with double-sided adhesive already applied. It isn't compatible with the factory automatic tow hitch, so rule it out if your X3 M has one. A second SQ-style X3 M diffuser is listed in pre-preg carbon, but its listing gives little beyond LCI fitment, so ask us how it compares.
X4M LCI diffusers, with or without a brake light
BMW gave the X4 M a new rear bumper with the facelift, built around a wide, anvil-shaped insert, and both X4 M diffusers here are listed for LCI cars from 2022 to 2025. Each is pre-preg dry carbon with a high-gloss finish, mounts to the OEM points and needs no drilling. The version with a brake light takes power from the existing taillight through the included plug-and-play harness, and its listing recommends a professional installer, especially for the wiring. The version without the light skips the wiring altogether.
Whichever you choose, test-fit it before painting or installing. If a diffuser doesn't fit the car on its product page, contact us before installing and we'll cover the return shipping for a refund or replacement. To match the top of the rear, see the X3M/X4M LCI spoilers.
Frequently asked questions
Does the Unit 17 X3M diffuser fit a pre-LCI car?
Yes. Our 3-piece diffuser with rear corner splitters is listed for the X3 M both before and after the facelift, so one kit covers pre-LCI and LCI cars. It is not made for the X4 M. The SOOQOO and SQ-style X3 M diffusers on this page are listed for LCI cars only.
Can I keep my X3M's tow hitch with a carbon diffuser?
It depends on the diffuser. The SOOQOO 3-piece isn't compatible with the factory automatic tow hitch. The other listings don't mention a hitch either way, so if your car has one, text a photo of the rear to 609-525-4865 and we'll check before you order.
How is the X4M diffuser brake light wired?
It connects to the existing taillight for power, using the plug-and-play harness supplied with the diffuser. The diffuser itself mounts to the OEM points with no drilling. The listing recommends professional installation, particularly for the brake light wiring and the final fit.