The Tesla Cybertruck achieves its futuristic looks with modern lighting elements and its slab-sided stainless steel design. Naturally, it needed a wheel and tire package to match. To that end, Tesla designed a set of wheel covers for the model to complete the chunky cyberpunk aesthetic. Except, it hasn’t worked out so well.
Forum users on the Cybertruck Owners Club Forums have been reporting that Cybertrucks have been shipping without wheel covers at all in recent months. “I was delivered my CT on the 24th without covers,” said ConcreteTilt. “Tomorrow is the 1st and I just received another message that they won’t be delivering because they are investigating all the covers and they won’t be delivering the caps until March.” Some noted they’d been advised Tesla had undertaken a “parts containment pending new revision,” while others noted they’d been advised the covers are currently backordered. There’s no recall in place though—the NHTSA presently has nothing on file for the Cybertruck.
It turns out this may be due to a very simple problem. Brian from YouTube channel T Sportline has an excellent explainer that shows us what’s going on. It’s all down to those seven rectangular “spokes” set into the Cybertruck’s wheel covers. Or, more accurately, the rubber extensions that protrude out from each “spoke” of the wheel cover.
Brian starts by pointing to one of the protrusions where it sticks out past the rim and over the tire sidewall. He notes they’re flexible, made of a different material to the hard plastic of the main wheel cover itself. Near the top of the tire, the rubbery extension has a small gap—maybe 1/8th of an inch or so—to the tire sidewall. However, at the bottom of the tire, it’s a different story. Here, the tire bulges out slightly thanks to the weight of the vehicle. In this position, the rubbery extensions can be seen touching the sidewall, or even slightly digging into it. With a few thousand miles on Brian’s Cybertruck, there are already visible marks gouged into the sidewall in the area of each protrusion.
It’s worth noting that each wheel of the Cybertruck has seven of these protrusions. Furthermore, depending on tire pressures and load and so on, each one could be pressing itself into the sidewall on every rotation of the tire. Now, let’s do the math. Take a Cybertruck on its standard 33.5″ diameter tires, doing 60 mph. That wheel is doing around 10 rotations per second, or 600 rpm. Each spoke could be poking the tire sidewall 600 times a minute on the highway. Just a little, but it’s happening.
It’s a unique problem for the Cybertruck, given that the futuristic wheel covers are a design statement for the model. It’s kind of surprising that Tesla didn’t discover this issue in testing. It’s kind of like when your friend goes to Autozone and fits cut springs and plastic flares to their car. You have to expect something’s going to rub, and you need to check.
It may have been that test mules ran without the wheel covers, or that the damage simply wasn’t noticed. It’s worth noting that it may have taken some time for a wheel cover to wear through a tire enough to cause serious damage or a loss of pressure.
It’s true that you’d have to chew out a lot of sidewall to cause a leak. But really, who wants to find out? Ultimately, it’s not safe to have something chewing through the rubber like that, let alone at multiple points on each tire. Anyone concerned about the matter should consider removing the wheel covers. There may be a small aerodynamic penalty involved, but it’s probably safer than having them poking into the tire sidewall on every rotation.
It’s not the only problem the covers have had, either. Electrek noted the case of a production candidate Cybertruck in September last year that saw its wheel cover fly off while driving on San Francisco’s 101 Highway. Despite flying through the air, thankfully, the cover did not appear to cause immediate harm to surrounding traffic. It’s possible that this issue may have been related—it’s easy to imagine a tire undergoing compression, with the bulge pushing into the cover and popping it off the rim.
Amusingly, Brian notes there is one small benefit of this problem. Owners that have the offending wheel covers now likely have a rare, “limited edition” accessory now that Tesla is likely changing the design.
Here’s the deal. If you’re fitting wheel covers of any kind, you need to check clearance. If you’re a young engineer, or just a bad one, take particular heed. You don’t just go up to the vehicle, whip out a ruler, and check the gap in one spot, and call it good. You have to check it all over, at each spot. You have to remember that cars are dynamic things. You have to understand things like tire deformation. Then you have to check and account for them. Even if you forget all this, simple testing and observation will reveal what you missed.
In any case, we’ll be interested to see how Tesla redesigns the wheel covers to avoid this problem. Can it save the protrusions, or will it abandon them entirely? If it were my company, I’d just go with turbofans and just rad the thing up. Just my two cents.
Image credits: Tesla, T Sportline – Tesla Upgrades & Accessories via YouTube Screenshot