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Rear Diffuser

Adding a more aggressive rear diffuser to your BMW can offer some performance benefits, but is primarily an aesthetic upgrade. BMWs naturally look great from the rear, why not make yours look even better?
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ECS - Corporate Logo
T#:391782
Part#: E46CSLCFDIFF
Back Ordered
Sale - Save 5% $ 515.99

This product was last offered at the strikethrough price on
06-13-2026

$ 490.19 USD
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Sale - Save 5%
$ 515.99

This product was last offered at the strikethrough price on
06-13-2026

$ 490.19 USD
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Half carbon diffuser to complete your CSL look
ECS - Corporate Logo
T#:20815172
Part#: 047616LA01KT
In Stock
Sale - Save 15% $ 520.99

This product was last offered at the strikethrough price on
06-14-2026

$ 442.84 USD
Free Shipping
Sale - Save 15%
$ 520.99

This product was last offered at the strikethrough price on
06-14-2026

$ 442.84 USD
Free Shipping

ECS Exclusive Proudly Offered at Turner Motorsport!

Add-on diffuser to deliver a true motorsport look to your M3. Fastened seamlessly to the bottom of the rear bumper giving a platform to show off your exhaust and complete the rear end of the E46.

The E46 M3 is an amazing looking car right out of the box but a common BMW issue is the height of the front vs rear bumpers. As far back as the E30, the front bumper is much lower than the rear bumper and the E46 M3 faces the same issue. With this problem the front bumper is always super low to the ground and the rear bumper looks in-complete. The ECS add-on diffuser is a unique option for balancing out the rear bumper with the height of the front bumper for a full and complete look.

Give your M3 that wild style that stands out from the crowd, and obtain a nice balanced look. This is just the start of a new line of Street Flow Diffusers diffusers that are a must have extension of your awesome ride. The diffusers come powder coated in a sleek satin-black finish, are a blast to install and fit seamlessly against the rear bumper for a professional looking install every time. The Street Flow diffuser attaches below your factory rear diffuser and exhaust of your choosing to fill out the rear end for a nice full and aggressive styling profile.

Lets take a trip together down a new and unique path. Over the years ECS has designed factory replacement ABS and Carbon Fiber diffusers for all different models of BMW's. For the factory replacements ECS focus was to take the oem characteristics and add a twist and really bring out a more aggressive look with a direct replacement diffuser. For their new line of diffusers, us as car enthusiasts wanted to design a set of diffusers that really pushed the envelope and stepped outside of our comfort zone. Our new line of add-on diffusers is a result of our engineering team and fellow enthusiasts spending time study the M3 chassis, modeling different designs, testing prototypes and making changes to get a final product that we are extremely excited to offer. The E46 M3 Street Flow Diffuser is the first in our line of new diffusers. Stay tuned for the E36 M3 and the E92 M3 diffusers next!

Features:

Adds an aggressive aesthetic in addition to the subtle factory rear diffuser
Lightweight and durable 10ga aluminum in satin black powder coat to blend with the factory trim color
Installation is secure and simple with ample adjustability built in for perfect fitment
Design:

10 ga 5052 aluminum construction
Black satin powder coat for long term corrosion resistance
5 piece design to simplify installation
Slotted mounting locations to allow for mounting adjustment
Laser cut ECS logo pre powder coat for a smooth finish
Hidden hardware for better aesthetic

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ECS - Corporate Logo
T#:2408497
Part#: 51747330558
In Stock
Sale - Save 11% $ 336.99

This product was last offered at the strikethrough price on
06-14-2026

$ 299.99 USD
Free Shipping
Sale - Save 11%
$ 336.99

This product was last offered at the strikethrough price on
06-14-2026

$ 299.99 USD
Free Shipping

ECS - Corporate Logo
T#:24179121
Part#: 047898LA01KT
In Stock
Sale - Save 10% $ 448.99

This product was last offered at the strikethrough price on
06-14-2026

$ 404.09 USD
Free Shipping
Sale - Save 10%
$ 448.99

This product was last offered at the strikethrough price on
06-14-2026

$ 404.09 USD
Free Shipping

ECS Exclusive Proudly Offered at Turner Motorsport!

Add-on diffuser to deliver a true motorsport look to your M3. Fastened seamlessly to the bottom of the rear bumper giving a platform to show off your exhaust and complete the rear end of the E92.

The E92 M3 is an amazing looking car right out of the box but a common BMW issue is the height of the front vs rear bumpers. As far back as the E30, the front bumper is much lower than the rear bumper and the E92 M3 faces the same issue. With this problem the front bumper is always super low to the ground and the rear bumper looks in-complete. The ECS add-on diffuser is a unique option for balancing out the rear bumper with the height of the front bumper for a full and complete look. The E92 diffuser also features an optional center fin design to dial in the aesthetic you prefer!

Give your M3 that wild style that stands out from the crowd, and obtain a nice balanced look. This is just the start of a new line of Street Flow Diffusers diffusers that are a must have extension of your awesome ride. The diffusers come powder coated in a sleek satin-black finish, are a blast to install and fit seamlessly against the rear bumper for a professional looking install every time. The Street Flow diffuser attaches below your factory rear diffuser and exhaust of your choosing to fill out the rear end for a nice full and aggressive styling profile.

Lets take a trip together down a new and unique path. Over the years ECS has designed factory replacement ABS and Carbon Fiber diffusers for all different models of BMW's. For the factory replacements ECS focus was to take the oem characteristics and add a twist and really bring out a more aggressive look with a direct replacement diffuser. For their new line of diffusers, us as car enthusiasts wanted to design a set of diffusers that really pushed the envelope and stepped outside of the comfort zone. ECS's new line of add-on diffusers is a result of the engineering team and fellow enthusiasts spending time study the M3 chassis, modeling different designs, testing prototypes and making changes to get a final product that we are extremely excited to offer. The E92 M3 Street Flow Diffuser is part of a new line of diffusers. Check out the diffusers in the line-up including the E36 and the E46 M3 variations!

Features:

Optional center fin included
Adds an aggressive aesthetic in addition to the subtle factory rear diffuser
Lightweight and durable 10ga aluminum in satin black powder coat to blend with the factory trim color
Installation is secure and simple with ample adjustability built in for perfect fitment
Design:

10 ga 5052 aluminum construction
Black satin powder coat for long term corrosion resistance
5 piece design to simplify installation
Slotted mounting locations to allow for mounting adjustment
Laser cut ECS logo pre powder coat for a smooth finish
Hidden hardware for better aesthetic

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ECS - Corporate Logo
T#:638447
Part#: E9XM33DCFDIF
Back Ordered
$ 578.99 USD
Free Shipping
$ 578.99 USD
Free Shipping
Looking to add a bit of aggressive styling to your BMW? The ECS Tuning Carbon Fiber Rear Diffuser is just what you need! Featuring a UV-resistant clear coat and 2x2 style carbon weave, this diffuser is the perfect addition to make your M3 stand out.
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ECS - Corporate Logo
T#:383337
Part#: 012196ECS12A
Back Ordered
Sale - Save 10% $ 340.99

This product was last offered at the strikethrough price on
06-13-2026

$ 306.89 USD
Free Shipping
Sale - Save 10%
$ 340.99

This product was last offered at the strikethrough price on
06-13-2026

$ 306.89 USD
Free Shipping

BMW Performance Style Rear Diffuser

Enhance the rear aesthetics of your BMW with a striking BMW Performance Style Rear Diffuser. Whether you're replacing an original or complementing your existing bumper, this diffuser exudes an aggressive style that stands out. Designed to accentuate your vehicle's rear while following its natural lines, it ensures a distinctive appearance. Enjoy a hassle-free installation with guaranteed fitment, elevating your BMW's visual appeal effortlessly.

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Akrapovic - Corporate Logo
T#:558675
Part#: DI-BM/CA/5/G/RS
Back Ordered
$ 1,931.99 USD
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$ 1,931.99 USD
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The Akrapovic Evolution and Slip-On line exhaust systems can be further enhanced with an optional hand-crafted carbon-fiber rear diffuser. Developed by Akrapovic’s Design Department, this stunning diffuser, crafted from materials developed through Akrapovic’s racing involvement, is designed to perfectly fit the lines of the unique tailpipes of the Slip-On or Evolution systems, as well as complement the sleek and sporty shape of the F90 M5 BMW.

**High Gloss finish with a red and white Akrapovic logo

This item fits the following BMWs: 
2018+ F90 BMW M5

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ECS - Corporate Logo
T#:10128411
Part#: 51747330558GB
In Stock
Sale - Save 11% $ 336.99

This product was last offered at the strikethrough price on
06-14-2026

$ 299.99 USD
Free Shipping
Sale - Save 11%
$ 336.99

This product was last offered at the strikethrough price on
06-14-2026

$ 299.99 USD
Free Shipping

Upgrade your MINI's appearance with the JCW GP II Rear Diffuser Kit, designed to add a high-performance look to your vehicle. This kit allows you to seamlessly integrate the JCW GP II rear diffuser with the JCW Aero rear bumper section, enhancing the overall aesthetic of your MINI. Designed to match the gloss black JCW aero kit trims, this kit includes textured OEM finishes on the underside to maintain a Genuine MINI look. Whether you're adding it to a stock JCW bumper or pairing it with other gloss black accessories, this kit ensures a sleek and cohesive design.

  • Adds a high-performance look to your MINI
  • Seamless integration with JCW Aero rear bumper section
  • Matches gloss black JCW aero kit trims
  • Textured OEM finish maintains Genuine MINI appearance
  • Includes all necessary brackets and hardware for installation
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ECS - Corporate Logo
T#:383336
Part#: 012196ECS11A
In Stock
Sale - Save 21% $ 327.99

This product was last offered at the strikethrough price on
06-13-2026

$ 258.99 USD
Limited Qty Sale
Free Shipping
Sale - Save 21%
$ 327.99

This product was last offered at the strikethrough price on
06-13-2026

$ 258.99 USD
Limited Qty Sale
Free Shipping

Upgrade your BMW F30's appearance with the BMW F30 M Performance Style Diffuser - Quad Exhaust. This high-quality diffuser is designed to replicate the sleek styling of the M Performance models, enhancing the look of your BMW F30. With its quad exhaust design and precise fitment, this diffuser is a perfect choice for those seeking to add a sporty touch to their vehicle.

  • Replicates the sleek styling of the M Performance models
  • Enhances the appearance of your BMW F30
  • Quad exhaust design for a sporty look
  • Precise fitment ensures easy installation
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