Maxton Design Street Pro Rear Diffuser with Flaps – BMW 4 Series Gran Coupé (F36) – Black/Red with Gloss Flaps
Give your F36 Gran Coupé a sharper, motorsport-inspired rear with this Street Pro diffuser and gloss flaps set. It adds a bold Black-Red centre detail with high-gloss side flaps, and is shaped to tidy the airflow leaving the rear of the car.
Designed for a direct fit to the BMW 4 Series Gran Coupé F36 (2014-2017). Please use our vehicle lookup to confirm fitment or check the Vehicle Fitment tab for full details.
Made from 10 mm ABS plastic, it is tough, impact and scratch resistant, and finished with a UV-stable coating to help prevent fading. The part is temperature and weather resistant for daily use. It arrives vacuum sealed with a protective film and features authenticity labelling. No painting is required.
The diffuser channels air under the bumper to improve stability at higher speeds. Expect a subtle change in feel rather than a dramatic performance gain.
What you get
- Maxton Design Street Pro rear diffuser with gloss flaps
- Mounting kit
Key features
- 10 mm ABS construction for strength and durability
- Black-Red core with gloss flaps for a premium look
- UV, temperature and weather resistant
- TUV MATERIALGUTACHTEN certified material
Important: Professional fitting is recommended. Ensure adequate clearance around the exhaust and secure all fixings. If you choose to paint the product, use primer first.
Choosing a Kit
Our vehicle registration lookup system cannot detect factory trim level. It is important for customers to check the specification of their own vehicle against the product description, and if their vehicle has an existing sports trim level, body kit or factory enhancement that may cause it to look different from other similar models.
For example: Volkswagen R-Line, BMW M-Power/M-Pack, Audi S-Line, Ford ST-Line, Merc AMG-Line, Seat FR.
These kits will not fit models that don't meet these specifications.
Returns
Purchased the incorrect kit for your vehicle? Or not sure you like the surface finish when it arrives? No problem!
Maxton Design products are eligible for return if the product has not been fitted, drilled, modified or damaged in any other way and still has the protective factory film intact. Unfortunately, there are no exceptions, this applies to fully removed and partially removed films.
Products with a protective film in place are clearly marked with this sticker, if you believe there to be an issue with the product but you can't tell without removing the film, please contact our support team directly for assistance.
DO NOT REMOVE THE FACTORY FILM UNTIL YOU'VE LINED IT UP, AND YOU'RE READY TO FIT THE PART.
See our Terms & Conditions for more information.
Installation & Fitting
Instructions & Guides
Maxton Design provide either an online reference (below) or printed instructions with their products, we can't stress enough how important it is to follow these guidelines. Not only does this create a safe, aesthetically well fitted product, but it increases the longevity and lifespan of the kit.
Neither Progressive Parts nor Maxton Design will be able to provide and support or warranty for products fitted incorrectly. For example, front splitters require the front bumper to be removed, without doing so the bolts will be incorrectly positioned and may not be able to cope with the down-force exerted on it. Straying from the guidelines in this manner must be done so at the owners risk.
Fibreglass & "Non-Prepped" Products
By adding these products to your basket you are agreeing to the below statement.
All Maxton Design Fibreglass products including certain bumpers, spoilers, spoiler extensions and skirts will require “prep” before installing.
These are not a simple 'ready to fit' modification. In transit, the items may get chipped or marked and as such prior to painting it is important you understand that the parts may require filling, sanding and repairing (defined "prep") prior to paint being applied, which can be undertaken by any reputable body shop at minimal cost.
Return requests based on not anticipating the definition above are not accepted, please be aware you have agreed to this statement and the definition of “prep” work required prior to purchasing.
Product images shown for sale often indicate a finished product, the colour shown on the vehicle is for illustration purposes.
Fitting Manuals
Please note, Maxton Design products are only available for UK shipping.
Including Northern Ireland, Scottish Highlands and Channel Isles. Delivery fees apply.









