From different experiments I’ve seen on X/Twitter and YouTube, it’s pretty clear that the Cybertruck has decent range and charging speeds. It’s also going to get even better when more 800-volt stations open to it. But one thing I hadn’t come across yet were Cybertruck towing tests. Like most EVs, there’s plenty of torque, but how much range can you get using that excellent torque?
Thanks to a couple of YouTube videos, we now have a much better idea of how it performs pulling heavy loads.
This first video gives us an idea of how the Cybertruck would perform for many people who take it easy and don’t try to max out the GVWR:
While the metal sides on an Airstream are generally a great match for the metal sides on the truck, this owner blacked his out. But, black and silver go good together, so it’s cool.
The trailer has a curb weight of about 6400 pounds. All loaded up with gear, though, it’s more like 7300 pounds. When he got it weighed, it came in at 6557 pounds. With two axles, it’s probably got a GVWR of 7500+, so that’s a safe load. One thing that’s really cool about this camper is that it has a large door on the back that opens, kind of like a miniature toy hauler. This makes it easy to load in that 1,000 pounds of cargo with things like bikes, motorcycles, and more. It’s also nice for opening up for fresh air and enjoying the outdoors.
They hooked it up to the Cybertruck to see how it tows. While many people think this is a very aerodynamic load, it’s really not fantastic compared to folding campers or teardrops. Rounded corners help with frontal area, but the relatively flat back still makes for a big vacuum zone that adds a lot of drag. I don’t say this to bash on Airliners (they’re pretty cool) as much as to explain that this is a very fair test. It’s not an underhanded throw meant to make the truck look good.
But — keep in mind that this is California. Towing in other states where you can go 65 instead of 55 might mean less range.
After 52 miles of towing, the total energy used was 46 kWh, with average consumption at 893 Wh/mile. Extrapolated out to 123 kWh, that means the truck would have a range of about 137 miles towing this much weight on such terrain. There was plenty of range to go back, but he stopped at a Supercharger to get back up to 80% so it wouldn’t be a nail-biter.
On the way back, his efficiency was better (638 Wh/mile), so the real figure to get an accurate average range would be for the round trip. Averaging the efficiency, that’s about 766 Wh/mile, which would make for an average range of about 160 miles. That average would be about right for level ground (because we averaged the uphill and downhill).
However, if you’re looking at planning trips, I wouldn’t use these numbers. Anything from temperature to terrain to headwinds can throw this all out of whack. It’s best to get a calibrated efficiency figure using an app like A Better Route Planner and let it do some of the guesswork to plan trips with a trailer. Also, it’s best to not be too crazy and plan to arrive at Superchargers with a dead battery when towing, because shifting winds can ruin your day. Keep 10–20% buffer for safety (plus, that’s better for your battery).
Another great towing test came from Out of Spec. They pushed the truck to its limits:
For this one, they took the truck on the “Rustic Ring” test loop through flat lands and mountains, including some slippery dirt. The test ballast? A Rivian R1T! As you can see close to the beginning, the Cybertruck did struggle a bit on the steep inclines, but managed to claw its way up. He did notice that you need to be gentle with the steering, because it’s pretty tight for a tow vehicle. Tesla may need to adjust this in an update (which is possible because it’s steer by wire).
What makes this tough is that there are both climbs and steep descents, both of which put a lot of stress on the battery, drive units, and cooling systems. This puts some trucks into their thermal limits, which can be dangerous because you have to rely on brakes for downhill segments, which might overheat them if you’re not smart about it or take a break.
He got maximum regenerative braking even with 73% state of charge. He had to use his friction brakes a lot, along with trailer brakes. This became a thermal limit after not very long, which led to using even more friction brakes. Eventually, most regenerative braking was lost. So, the key lesson is that you really need trailer brakes with the Cybertruck if you’re going to haul 10,000 lb in the mountains with steep climbs followed by steep descents.
On the slippery section, it did great, though. It did slip, but gripped and pulled on up despite carrying more of a load than most people would. One thing Kyle noticed was that the Cybertruck seems to want to put more power to the front wheels until it slips, and then it goes ahead and gives more power to the rear.
Back on pavement, it was time for downhill descent and braking again. It didn’t take very long to start seeing limited regenerative braking again. He points out that this was an issue with the Rivian he did descent towing testing with, too, so this isn’t some major problem unique to the Cybertruck (and people think I hate Tesla, but I’m honest). This does present a problem that might be solved at least partially with an update, but it’s probably a protective measure that’s unrelated to thermal management (IOW, the battery is probably not getting too hot).
Hopefully other trucks do better, and we’ll find out because he’s going to put other trucks through this same course.
I don’t want to be an alarmist, but the brake issue is something people towing heavy loads with the Cybertruck need to be aware of and consider, because it could get you into trouble on longer, steeper descents. At one point, Kyle said he smelled the brakes, and that’s NOT something you want to experience while towing, because you’re on the road to failure.
Sadly, many people don’t know that it’s not normal to ride brakes when descending steep mountain roads. In a little car, you’ll experience premature wear, but when you’re using the brakes to control almost 17,000 pounds, you can overheat the brakes like that and lose them. On a twisty mountain road, that could mean you die and take several other people with you.
For this reason, ICE tow vehicles (and anybody intelligently operating any vehicle on steep descents) use engine braking to control speed, shedding heat and energy through the vehicle’s radiator instead of only through the friction brakes. For EVs, being able to put energy back into the pack is the safe way to accomplish this.
But, again, I’m not trying to bash the Cybertruck when pointing this out. It’s just something you need to be aware of if you’re going to tow anything heavy down steep grades and account for to keep safe. For this reason, trailer brakes are going to be very important. If you find yourself smelling brakes, you definitely need to find a place to stop and let them cool off to avoid getting into brake fade and loss of brakes.
Featured image: screenshot from the Out of Spec video embedded above.
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