SKU: 73603684450

MMX Performance Coolant Expansion Cap 90mm - BMW

$88.44 $98.27
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Ships within 48 hours · Estimated delivery Aug 1 - Aug 6

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Description

MMX Performance Coolant Expansion Cap 90mm - BMWThe MMX Performance 90mm billet coolant expansion cap for BMWs has been designed from the ground up in the UK, from a solid piece of billet aluminium. Each cap was designed to directly replace the OE cap, not merely stuck in place. Fitment is for models with the matching OE (17 11 7 639 021) part number. Each MMX cap starts life as a solid billet of 6061 aerospace grade aluminium. It's meticulously machined from this billet with the latest CNC 5 axis

The MMX Performance 90mm billet coolant expansion cap for BMWs has been designed from the ground up in the UK, from a solid piece of billet aluminium.
Each cap was designed to directly replace the OE cap, not merely stuck in place. Fitment is for models with the matching OE (17 11 7 639 021) part number.
Each MMX cap starts life as a solid billet of 6061 aerospace-grade aluminium. It's meticulously machined from this billet with the latest CNC 5-axis technology, before being polished, then gloss-anodised to stay beautiful year after year.

All MMX coolant caps arrive pre-sealed and pre-installed with an OE spec valve and internal spring. No need to remove the valve assembly from your OE cap. A true plug and play solution.

It has been designed to instantly give your BMW an under-bonnet boost in the aesthetic department, finished in a deep gloss black anodised finish.

Never again will you worry whether you tightened your expansion cap fully, as the cap contains complete OE replacement internals. The carefully considered design gives ample surface grip area for your fingers, making installation and filling your coolant that little bit easier.

It joins an existing range of engine dress-up products for a complete under-bonnet transformation to your engine bay.

Feature heavy:
· Designed and engineered in the UK

· Crafted from 6061 aerospace-grade aluminium

· Full OE cap replacement

· Sophisticated internal springing and bleed off

· Anodised in MMX signature gloss black

· Joins existing range of MMX billet caps

· Pre-installed factory spec Viton O-Ring

 

Please check the underside of your factory expansion cap for the OE part number. It’s a larger cap, measuring roughly 90mm in diameter. The MMX billet coolant expansion cap for BMW fits OE part number 17 11 7 639 021.

Please note if the part is under excessive heat for prolonged periods of time, it can affect the overall finish, which is unavoidable with anodised aluminium products.

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 73603684450

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4.7 ★★★★★
Based on 13 reviews
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Product Reviews
J
Verified Purchase
Jeff
Natrona Heights, US
★★★★★ 5
this 27mm oil filter socket – it’s incredible. It’s the best.
Size: 27mm, Color: Red, Size: 27mm, Color: Red
Let me tell you something, folks – nobody changes oil like I change oil. Nobody. I’ve been around the best cars, the best mechanics, and let me just say, this 27mm oil filter socket – it’s incredible. It’s the best. I don’t know who made it, but I have to say, it’s tremendous. You know, people always ask me, "how do you do it? How do you change oil so perfectly?” And I tell them – it’s the tools. This socket is the reason why I can change oil faster and better than anyone. It fits perfectly on the filter, like it was made just for me, like everything else in my life. You slide it on, you give it a twist, and boom, you're done. It’s like magic – but not really, because magic is for others. This is skill. This is expertise. This is the power of the greatest tool ever made. You won’t find a better oil filter socket wrench. This tool makes you a winner. It’s precision-engineered, like the T-ump Tower of oil filter wrenches – big, strong, and reliable. And the best part? It’ll last forever. I’ve used it on many cars, and every time, it gets the job done with style. People will look at your work and say, “Who changed that oil? That’s perfect.” And you’ll know – it’s all because of the best socket out there. So, if you want to change oil like the greatest – you need this socket. It’s unbeatable. Believe me. You'll never go back to anything else
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 24, 2025
J
Verified Purchase
Jason
Belleville, US
★★★★★ 5
Fits perfectly
Size: 32mm, Color: Green
Works exactly as expected. Fits the 32mm oil filter housing perfectly and makes removal quick without slipping or rounding. Feels solid and well-made for the price. Used it for an oil change and it saved a lot of time compared to a strap wrench. Simple, effective tool—glad I bought it.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 28, 2026
M
Verified Purchase
Mayelin Naranjo terga
West Palm Beach, US
★★★★★ 5
worked for my dodge.
Size: 28mm, Color: Red
worked for my dodge. light but needs to not be so strong as to brake the plastic. seems like it will keep the plastic in tact and not kill it. nice and bright green i can find it easy.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 21, 2026
R
Verified Purchase
Riley Smith
San Leandro, US
★★★★★ 5
Perfect Fit 28mm Fuel Filter Socket
Size: 28mm, Color: Red
I bought the Felisbieti 28mm fuel filter socket for a vehicle maintenance project, and it worked perfectly. The fit is precise, gripping the fuel filter securely without slipping or rounding edges. The build feels sturdy and durable, with a solid metal finish that stands up to repeated use. It fits snugly on my ratchet and made removing and installing the filter much easier and faster than using adjustable tools. The only minor thing to note is that it’s specific to 28mm filters, so make sure it matches your vehicle. Overall, this socket is well-made, reliable, and a must-have for anyone doing DIY fuel filter work.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 27, 2025
R
Verified Purchase
Rowdy Yates
Port Orchard, US
★★★★★ 5
Perfect socket for the job
Size: 24mm, Color: Green, Size: 24mm, Color: Green
I purchased this 24mm socket specificaly to remove the oil filter housing on my Ram Promaster 2500 truck. Since there is limited space to get a standard socket in this area, this low profile socket was able to do the job without requiring me to loosen and push aside other components. I like that this socket is light weight, made of aluminum with large easy to read size eched into the body. the oil filter housing is made of plastic and does not require a beefy heavy steel socket. The walls on this socket are plenty thick as to cause me no concern about durability. To me, the green color is a nice touch as will be easy to spot in my socket set for the oil changes.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 28, 2026

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