00:00These wheel spacers start as aluminum stock and go through forging, heat treatment, CNC machining,
00:06and final inspection before they reach a Tesla Model S.
00:09But what makes an active cooling wheel spacer different from a conventional design?
00:13Let's follow the manufacturing process, take a closer look at the details,
00:18and see how the finished spacer fits this 2017 Model S.
00:22At first glance, a wheel spacer might look like a simple piece of metal,
00:26but its dimensions and contact surfaces matter.
00:29This Bonas spacer uses a forged AL6061-T6 aluminum body with machined mounting surfaces,
00:37a hub-centric locating feature, and dedicated mounting hardware.
00:41On the back, you'll also notice the active cooling groove design.
00:45These grooves are intended to help guide airflow around the spacer as the wheel rotates.
00:50To understand how those features are made,
00:52we need to go back to the beginning of the manufacturing process.
00:56The process begins with aluminum stock.
00:59The material is cut into blanks sized for the next manufacturing stage.
01:03At this point, the blank doesn't have the final shape, mounting profile, or cooling grooves.
01:09It's simply the starting material for a much more controlled process.
01:13The goal is to prepare a consistent blank before moving on to forging.
01:17Next comes forging.
01:46Forging
01:48CNC machining brings the spacer closer to its final dimensions.
01:52The first operations establish the basic shape and reference surfaces.
01:56Then, the machine works on the mounting geometry, including the bolt pattern,
02:01center bore, and hub-centric locating features.
02:03These dimensions need to match the intended vehicle and wheel configuration.
02:08For this Model S application, the relevant fitment specifications include a 5x120 bolt pattern
02:15and a 64.1mm center bore.
02:18The active cooling grooves are also machined into the design.
02:21This is where the design becomes a finished, vehicle-specific component rather than just a
02:26shaped piece of aluminum.
02:28After machining, the spacer moves to surface finishing.
02:31The hard anodizing process creates an oxide layer on the aluminum surface.
02:36Depending on the specified process, this can improve surface hardness and wear resistance.
02:41The finished part is then marked and inspected.
02:44Now let's bring the finished spacer back to the car.
02:47The spacer must sit flat against the hub, and the wheel must seat correctly against the spacer.
02:52This 2017 Tesla Model S uses a front setup of 15mm and a rear setup of 20mm.
03:00So what makes this an active cooling design?
03:02As the wheel rotates, the grooves work like an impeller.
03:06They pull air across the spacer's back surface and push it toward the brake rotor and caliper.
03:11Every single rotation moves hot air away and feeds cooler air in.
03:16The design is patented.
03:18And this is where manufacturing matters.
03:20Every groove is CNC milled into the forged body.
03:23You can see the tool paths.
03:25That depth and spacing is what makes the airflow work.
03:28You can't cast this geometry, you have to cut it.
03:31No electronics.
03:32No moving parts to fail.
03:34Just geometry, doing its job 10,000 times per trip.
03:38That's how a Bonas active cooling wheel spacer goes from aluminum stock to a finished component
03:43for this Tesla Model S.
03:45If you'd like to see more real-world fitment tests, engineering details, and manufacturing processes,
03:51subscribe to the channel.
03:52And if you're choosing wheel spacers for your own car,
03:55always verify the exact fitment before installation.
