BMW 3 Series G20 G21 LCI Carbon Fibre Performance Rear Diffuser Set by TRE (2023+) - AUTOID - Rear Diffusers - TRE

BMW 3 Series G20 G21 LCI Carbon Fibre Rear Diffuser Set by FORM (2023+)

$1,012.00
Sale price  $1,012.00 Regular price 
Skip to product information
BMW 3 Series G20 G21 LCI Carbon Fibre Performance Rear Diffuser Set by TRE (2023+) - AUTOID - Rear Diffusers - TRE
1/7

BMW 3 Series G20 G21 LCI Carbon Fibre Rear Diffuser Set by FORM (2023+)

SKU: FO-BG20LRDCFE
$1,012.00
Sale price  $1,012.00 Regular price 
2 Year Warranty
Fitment Guarantee
Genuine FORM Industries
1 left Order soon, limited stock remaining
Payment methods
  • American Express
  • Apple Pay
  • Google Pay
  • Klarna
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Introducing FORM

Introducing FORM

This product is now manufactured and supplied by FORM Industries, the dedicated brand for essential vehicle styling. Same quality and fitment as before, with a new name. Read more.

The FORM Industries Performance Rear Diffuser for the BMW 3 Series M Sport LCI has been made to provide an aggressive centre piece on the rear of the vehicle.

It is constructed from 3 pieces of pre-preg Carbon Fibre.

NOTE: This kit is for European cars only.

What's in the box
  • 3 x FORM Industries Carbon Fibre (pre-preg, 2x2 Weave) Rear Diffuser Pieces
Compatible models
  • BMW 3 Series LCI (2023+, G20 G21)

NOTE: This kit is for European cars only.

How to install

BMW G20 M Sport — FORM Industries 3-Piece Rear Diffuser Installation Guide

Difficulty: ★★☆☆☆ (Moderate)
Time Required: 30–45 minutes
Tools Needed:

  • Plastic trim removal tools

  • T20 Torx screwdriver

  • 8mm socket wrench

  • Microfiber towel or fender cover

  • Optional: a friend or second person for alignment assistance


Step 1: Prepare the Vehicle

  1. Park the vehicle on a flat surface and engage the parking brake.

  2. If possible, raise the rear of the car slightly using ramps or a lift for easier access.

  3. Use a microfiber towel or fender cover to protect the paint around the rear bumper.

  4. Ensure the diffuser and surrounding area are clean and free of dirt or debris—this prevents scratches during removal and installation.


Step 2: Remove the OEM Diffuser

  1. Begin by removing the screws along the underside of the OEM diffuser using an 8mm socket or T20 Torx driver, depending on your model.

  2. Once the screws are out, use a plastic trim removal tool to gently pry the diffuser away from the bumper.

  3. Work your way from one side to the other, carefully releasing the diffuser clips. Avoid using metal tools, as they can damage the bumper tabs.

  4. Once all clips are disengaged, pull the OEM diffuser straight out and set it aside.


Step 3: Test-Fit the FORM Industries Diffuser Pieces

  1. Before full installation, test-fit all three FORM Industries diffuser pieces (left, right, and center) to familiarize yourself with alignment and fitment.

  2. Check that all clip points and screw holes line up correctly with the factory mounting locations.

  3. If necessary, make small adjustments to ensure a flush, even fit before securing anything permanently.


Step 4: Install the FORM Industries Diffuser — Side Sections

  1. Begin with the left-side diffuser piece. Align the mounting tabs with the OEM clip points, then press firmly until all clips snap securely into place.

  2. Repeat the process on the right-side diffuser piece, confirming that both ends are evenly seated and flush with the bumper contours.

  3. Reinstall any factory screws along the lower edge of each side piece if applicable.


Step 5: Install the Center Section

  1. Align the center diffuser section between the two installed side pieces. Ensure that the edges overlap cleanly and that all clip points are fully engaged.

  2. Press upward and inward firmly until the center piece locks into place with an audible “click.”

  3. Reinstall the remaining screws along the underside of the diffuser to secure all three sections.

  4. Perform a final visual check—ensure all edges are even, clips are seated, and the diffuser sits flush with the bumper.


Final Notes

  • Recheck all clip points and screws after a short drive to ensure nothing has shifted.

  • For an OEM-like fitment, patience and even pressure during installation are key—avoid forcing any section into place.

  • If you plan to apply ceramic coating or PPF to the diffuser, do so before installation for the best finish.

About FORM Industries

FORM Industries is a refined approach to essential vehicle styling, built on products that have been developed, tested, and enjoyed by customers worldwide for over a decade. Created by an experienced design team, the brand focuses on clean, well-balanced components that enhance a car’s stance and presence through subtle, considered design rather than trends or excess.

Finance

Looking for a bit of flexibility when it comes to paying? We've got you covered. AUTOID has partnered with a number of payment providers to ensure a seamless buying experience.

Klarna
Select 'Klarna' at checkout to benefit from a number of finance options at checkout including:

  • Pay Later - Delay payment by up to 30 days, interest free
  • Split Payments - Split payments in 3 up to 3 months, interest free
  • Installments - Split payments up to 6 months interest-free, up to 24 months interest bearing.
  • 6 months - Interest-free Credit- Minimum: £250- Maximum: £5,000- 0% down payment/deposit​
  • 12 months - Interest-free Credit- Minimum: £250- Maximum: £5,000 Deposits are available and determined by the customer​:
    - 0% down payment for orders between £250 and £1000 (orders cannot be below £250)
    - 10% - 50% down payment for orders between £1000.01 and £5000
  • 24 months - Interest-bearing Credit - 18.9%- Minimum: £250- Maximum: £5,000
    Deposits are available and determined by the customer:
    - 0% down payment for orders between £250 and £1000 (orders cannot be below £250)
    - 10% - 50% down payment for orders between £1,000.01 and £5,000

Klarna's Pay in 3 / Pay in 30 days are unregulated credit agreements. Borrowing more than you can afford or paying late may negatively impact your financial status and ability to obtain credit. 18+, UK residents only. Subject to status. Ts&Csand late fees apply.

Clearpay
Clearpay lends you a fixed amount of credit to allow you to pay for your purchase over 4 instalments (T&C's and eligibility criteria apply). They're ideal for purchases under £1000 and always offer interest-free*. For more details on how to use Clearpay to secure your order, get in touch with our team.

0% Interest. Select 'Clearpay' at checkout.

Please shop responsibly and visit lender websites for more information. All finance options are suitable for individuals 18+.

You might also like

WHY BUY FROM AUTOID

AUTOID is the leading destination for BMW M, Audi & VW aftermarket styling & Premium Carbon fibre upgrades. From front splitters and rear diffusers to intakes, exhausts and interior accessories, we deliver only the highest quality parts that transform your cars look and feel. Trusted by thousands of enthusiasts worldwide and rated 4.85/5. We back our products up with expert advice, fast worldwide shipping and a passion for innovation & vehicle styling.

Shop now