SKU: 73603684450

MMX Performance Coolant Expansion Cap 90mm - BMW

Sale price$88.44 Regular price$98.27
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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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4.2 ★★★★★
Based on 11 reviews
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K
Verified Purchase
KAV
Carnegie, US
★★★★★ 2
Destroyed in under 10 minutes
Size: 9 in, Color: Large Bone
I bought 2 of these toys, one for my 9 year old great dane who isn't an aggressive chewer, and one for my 6 month old puppy who is average. In less than 10 minutes both were destroyed and my dane managed to swallow a good chunk. I wasn't surprised when they both had small holes on the ends and started pulling the stuffing out. The stuffing and squeakers were confiscated immediately, but I let them keep chewing. By the time I came back from throwing the insides away, both dogs had chewed the toys in half and my dane swallowed a chunk when he saw me coming. The puppy was going to do the same thing, but luckily we're working on his "drop" command so he was excited enough for the bigger payout and dropped it. They didn't just come apart at the seams, the whole toy ripped in half making it too easy to swallow. Neither of them are aggressive cheers and the toys didn't hold up at all. A stuffed animal toy would have lasted longer (and has any time I've allowed it). 10 minutes of playtime is probably too generous , but I'm trying to be fair. If I hadn't been right there watching them, they both would have been able to swallow the whole thing in minutes. Definitely not safe for any amount of actual chewing.
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Reviewed in the United States on November 14, 2025
S
Verified Purchase
Skylaire
San Leandro, US
★★★★★ 5
The perfect teething toy for a puppy of any size - apparently indestructible!
Size: 9 in, Color: Large Bone, Size: 9 in, Color: Large Bone
I ordered this product for an overly excitable, destructive corgi chihuahua mix puppy, who was teething. He was a foster and managed to destroy, almost immediately, every toy I had on-hand for him, and toys I picked up at the local pet store. I was very concerned he'd swallow parts of toys, which can lead to fatal intestinal blockages, not to mention extremely high vet bills which I couldn't cover as a simple foster mom. When it arrived, I crossed my fingers that the "Seam Protection - doubled-stitched seams with heavy duty thread" would actually add "extra durability." And I was NOT disappointed! The bone shape of the toy would probably fit comfortably in the mouth of any dog or puppy, as you can see from photo #4. What's coolest about the shape of this toy is the pup can sink all of his or her teeth into it, providing comfort for the entire mouth and not just a few teeth or only one section of its mouth at a time. I was much more experienced as a kitten foster mom, and had had similar difficulties finding teething toys for kittens. This toy is thin and light weight enough that I imagine it could provide relief for little kitten mouths, also, but I didn't get to find out, as my little foster pup chose this as his #1 favorite toy and brought it with him to his forever home. I wanted to know how long it would take before he'd destroy it, though (picture 5 he'd had this Dura-Fused bone toy for a few hours short of one week, and the last photo - you'll see he'd not even undone a small portion of the seam!) Overall I would highly recommend this product for teething babies of almost any species. As far as I could tell it is indestructible. Almost seven days of constant gnawing and he'd not even taken one stitch out, created any tear or rip, let alone, gotten close to being able to swallow the squeaker (always a fear!). I imagine months later, he's still been unsuccessful at ripping/tearing this toy at all. I'd gladly buy again should I foster any dog or puppy - the company lives up to its moniker, Ethical Products, because they've produced a no-frills and apparently indestructible squeak toy which I'd have no fears of leaving with a teething puppy unsupervised. Highly recommended!
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Reviewed in the United States on November 28, 2020
A
Verified Purchase
Amazon Customer
Natrona Heights, US
★★★★★ 3
Good tug toy
Size: 15 in, Color: Retriever
I have a doberman that shready everything in 2.5 seconds. This lasted a few days so was impressed for the cost. Would buy again as he really liked it.
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Reviewed in the United States on December 28, 2025
L
Verified Purchase
Larry B.
Lexington, US
★★★★★ 5
My dog’s new favorite
Size: 8 in, Color: Squirrel
didn’t expect much for the price but my dog actually loves this thing. It’s tough enough to hold up to regular chewing and the leather gives it a nice texture that’s different from the usual plush toys. He carries it around like it’s his prize. It’s not indestructible and if your dog is a heavy shredder it probably won’t last forever but for moderate chewers it holds up way better than a lot of toys I’ve tried. Definitely worth grabbing again.
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Reviewed in the United States on July 19, 2025
M
Verified Purchase
M
Massapequa, US
★★★★★ 4
Not for gnawers
Size: 11.5 in, Color: Bear
I was hoping this would work for my teenage ACD and save my leather goods from being chewed on. He gnawed on it quietly I was thrilled. But I had to take it from him within a few minutes. Gnawing apparently equals chewing pieces off. Not made for chewers or gnawers. It seemed to be well made, was soft, was actually a fairly good size and didn’t get gross when it got spitty. Just didn’t work out for Captain chaos destructor of all.
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Reviewed in the United States on May 4, 2026

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