okay, here we go. Yep, that's me, a towing newbie hauling 5,600 hands-free in the GMC Sierra EV Denali Edition 1. I'm on my way to the Milford Proving Grounds, which is the oldest automotive testing facility in the world, and it's where General Motors does a whole range of different testing on its vehicles. I am going to take you behind the scenes to actually drive on those test tracks in the newest EV pickup truck from GMC, and then I'm going to take you behind the scenes to see how it all comes [Music] together. The Proving Ground covers 4,000 acres and has over 140 miles of road, including special tracks to test ride and handling. Before rubber ever hits the road here, 17.5 million miles of virtual driving has already happened. Braking, steering, electrical systems, suspension, and battery are all tested in the lab, in simulators, and finally in the vehicle itself. Super Cruise, or hands-free driving, is the only system that lets you tow a trailer, and GM says it will work

on over 750,000 miles of liar mapped highways across the US and Canada by the end of 2025. Let's head back to the track to see it in action. If you want, let's say 55-60 MPH, whatever you're comfortable with. It does not feel like I've got a trailer behind me. This is wild. Okay, this is both terrifying and amazing at the same time. Time 55. Okay, here we are. All right, so now there's a little white steering wheel on the cluster that indicates we are on a mapped road for super cruise. So if you want to press the super cruise button, yep, right where your thumb is, go ahead and press that. It first turns blue and then quickly to green once it recognizes, and once it's green, you can let go with your hands, okay? And it will now control speed and steering. Okay, we weren't allowed to put cameras on the track to show you the outside shot of me towing that 20-ton trailer, but it looked something like this. Green lights on and, and you serious.

I take my everything off the no really yep just keep focusing oh my God okay vehicle will take care of the rest okay here we go my my feet AR my feet I can just sit back like this really that is wild I can't believe it you let me do this with a trailer this is really cool I on the road still but on the road y it's still monitoring you to make sure you're still here this is it's too easy it's too easy if I can do it just by pressing a button anyone can the ride and handling Loops evaluate everything from steering to suspension this is where I got to try out max power mode which unleashes 754 horsepower and 0 to 60 and less than 4.5 seconds and I brought a few colleagues along for the ride so get down to about 25 what we're going to do H all right go ahead Thor's hammer came out as us Engineers like to call it but this real world testing is only a small part of

the process. About 80% of the development is done virtually before a vehicle is even built. So we can do suspension tuning, we can do tire construction evaluation, all those types of things with a driver in a buck in a simulated environment. It simulates any road surface that we want to go out and map and take into account, and you can do a lot of that tuning before you ever get wheels on the road. And this actually has a full 6° of freedom, so it's going to be able to simulate pretty much every scenario you might end up in in the real world. The Sierra EV was originally specced to have over 400 miles of range, but it ended up being 440, making it the longest-range electric pickup so far, alongside the Chevy Silverado EV. Getting that 440-mile range out of the Sierra EV really does start at the battery level, and this is the Battery Systems lab here at GM where all of the development takes place. And it starts from the cell level, then to the module, and then to the battery pack.

that ends up in the final vehicle, and all the batteries go through extensive, rigorous testing, including some very extreme situations. We made a small innovation to this cell design, where it only has that folded seam on one edge, so this pouch is actually a single piece. It wraps around the electrodes, kind of like a taco. That means on the bottom, we've only got one layer of pouch to go through, and that's actually really easy to go through to get heat out. How you doing, Kevin? There are some special durability tests that replicate environments the battery might go through. This walk-in chamber is set to -68° C, and it runs for weeks on end to see what the power deviation is when the cells cool. It can also heat up to positive 68° to test performance in extreme heat. Okay, so this is the Mega Shaker. So this one will go from 0 to 2,000 htz. We can go up to 4,000 lbs of weight on here. If you're going on a

highway, and you're trying to simulate a 2-inch bump at 60 mph. That's a lot of inertia to control, and so that whole thing is literally shaking while the engineers are in that control room watching it. This lab has actual brake hardware, including brake calipers, lines, and hoses, combined with a virtual simulation of other parts of the truck. Engineers do validation testing for specific elements like one-pedal drive. This would normally take a driver days or weeks on end in the real world, but it takes only 30 to 50 hours in the lab. Every element is tested over and over again, from components in the infotainment system to the suspension. This is called a four-poster, and it's used to simulate road forces on the vehicle. So this test is actually testing a particular scenario where slabs are not level, and you're going through, and there's frost on the road, and it feels pretty smooth. That was a bump I wasn't expecting. All of this wiring is actually representative of what is in the Sierra.

EV obviously. It looks a little bit different to what's here, but this is also. Engineers can test the software in the vehicle before it goes into the evening itself. And here, around the front side of the bench, you'll see these circuits. And this is where Engineers can do all of their testing. They can introduce faults if they need to and basically make sure the software is doing what it's expected to do. And every single element of the vehicle is represented here. The software that controls the infotainment system, through to the safety systems, through to even the lighting right up here. That's all tested right on this bench. Even the Sierra ev's interior has gotten a high-tech makeover thanks to head-mounted displays or VR headsets. Designers use them alongside clay models to get a feel of the cabin before it's even built. So, at the beginning of the process, it helps us to just decide if the proportions are right or general location of like the steering wheel or screens. Are they okay? But then when you get to the end of the process where you

really have a detailed surface model like this. We can get into colored materials, changing the finishes on certain things, but it also allows us to sort of deep dive how parts fit and how you really feel in the environment. I've been driving the CR AV for the past few days, and what's really struck me the most is that at its heart, it truly just does feel like a pickup truck, despite all of the high-end technology inside. And it does feel like this is a pivotal moment for EV pickup trucks, with manufacturers like Rivian, Ford, Tesla, and of course GM placing big bets. I really do feel like this could be the time for EV trucks to cross over into the mainstream. Thanks so much for watching. I hope you enjoyed the episode as much as I enjoyed making it for you. You can find more about the Sierra EV and the development process in the link in the description below. I'll see you later.

I Towed 5,600 Pounds Hands-Free in the GMC Sierra EV Truck

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