Tesla Cybertrucks are now being delivered without aerodynamic wheel covers installed, due to the covers causing excessive wear and tear to tires. Tesla is currently redesigning the covers, with a fix coming soon™.
In the last couple days we’ve been hearing some scuttle that Cybertrucks were being delivered without aero wheel covers installed, due to some sort of problem with the covers. Now we know that the covers are causing unusual wear and tear to tire sidewalls, and that Tesla is going to stop delivering Cybertrucks with covers installed as they redesign them to fix the problem.
The Cybertruck has a pretty unique tire and wheel cover layout, with the both of them taking “angular” design cues from the vehicle. The covers have a six-pointed design, and each “point” fits into a recess on the tire sidewall designed to accept it.
But the reason for these wheel covers is not just design, but efficiency. Wheel covers can reduce aerodynamic disturbances by a large amount – think about it, you’ve basically got four turbines running blasting air out the sides of your car, air which would be better served by smoothly sweeping around the car, causing fewer disturbances.
The net effect of this is that cars with wheel covers on them can gain 5-10% more efficiency. Applied to the entire US vehicle fleet, we could probably reduce total US energy consumption (not just automative energy consumption, but overall) by ~1% if every car had wheel covers.
There still needs to be a little air coming through them to help pass over and cool the brakes, though, which is one reason why gas cars have had open spokes on their wheels. This is still necessary with EVs, but less so because EVs use regenerative braking, which means the friction brakes generate less heat and therefore aero covers need fewer “holes” in them than those on cars that use the friction brakes more often.
Because of this, there’s a small gap between the edge of the Cybertruck wheel cover and the tire, in order to allow some air to pass through. But as Cybertruck was nearing production, we saw that gap potentially cause a problem as a wheel cover flew off in traffic, causing potential safety issues for other road users.
But now, Cybertruck wheel covers seem to be too close to the tire, as they are rubbing against the sidewall during operation.
This can be seen in a video from Tsportline, a shop that sells customizations for Tesla vehicles, and explains the issue that has led to Cybertrucks being delivered without wheel covers.
What’s happening is that while driving, tires naturally flex outward at the bottom when contacting the road, and as the sidewall of the tire bulges outward, it contacts the edge of the aero wheel cover, which gradually wears down the tire. The wear is already visible on a car with a couple thousand miles on it, and the video says it has worn down by about 120 thousandths of an inch, which is a pretty massive amount of wear for just “a couple thousand miles,” when tires are meant to last tens of thousands of miles.
The video uses the word “recall,” but that’s not entirely the right word to use, because this isn’t an NHTSA recall. Tesla, for its part, is reportedly calling this a “parts containment pending revision,” and not using the word recall.
But it is something that owners should take action on by removing the aero covers for now until a fix is found. It’s also possible that the problem would be reduced by ensuring that you have well-inflated tires so that they don’t bulge out as much on the bottom while driving (this may not solve the problem – but you, yes you reading this, regardless of whether you have a Cybertruck, should check your tire pressures anyway because improper tire pressure is another thing that can reduce your range by ~10%, in gas cars as well).
The good news is that the sidewall isn’t as safety-critical as the tread of the tire, since it’s not contacting the road, but the sidewall is also thinner than the tread, which means if it gets worn enough to expose the cords of the tire then there could be some real problems. So don’t mess around, and take your wheel covers off until a fix is found.
As for the redesign, we don’t know when it is due because Tesla is famously uncommunicative about these sorts of things. Users over at the Cybertruck Owners’ Club claim that Tesla communicated with them that the new caps won’t be available until March, but we’ll have to wait and see.
Electrek’s Take
On the one hand, this isn’t that big of an issue – the cars still operate perfectly fine, and there’s an easy (temporary) fix for owners to just pop the covers off themselves, which can be done by hand.
But on the other hand, there have been a lot of other issues with the Cybertruck launch. It does tend to happen with Tesla launches, which are often rough in the beginning (though my early Model 3 has remained relatively problem-free, minus some early software glitches that have been improved upon dramatically via OTA updates), and the Cybertruck hasn’t been exceptionally bad in that respect.
The common issues of panel fitment have been documented many times online, and videos of stranded Cybertrucks are making the rounds. These sorts of videos are somewhat to be expected given the Cybertruck’s status as a vehicle that, no matter where it goes, is constantly being filmed, making it likely that any problem about it will blow up into a viral post.
But it still would be nice to have solved these issues before delivery – because we did know there were issues with the wheel covers, and because wheel covers are really important for efficiency, and I personally would love to see them become more accepted and more common on vehicles for that reason.