The Tesla load was 12 Jersey barriers. They weigh two tons apiece, so this rig was carrying a 48,000-pound load.
Now let's deal with the "it's guaranteed not to break down for a million miles" thing. Uhh...Elon...if you had bothered to research the industry you are trying to battering-ram yourself into with your stupid-looking truck, you would have learned that a million-mile transferable warranty is standard on a Class 8 tractor. There are at least seven brands of Class 8 truck on the road that have no Muskisms in their product line. They are Kenworth, Peterbilt, Volvo, Mack, International, Freightliner and Western Star. EVERY SINGLE TRUCK those companies build is guaranteed to not break down for a million miles. This is why trucking lines replace their entire fleets every four years - the unused warranty is a valuable asset.
This is what concerns me: The drive on a Tesla Semi is four motors taken from the Model 3, one per drive wheel. These motors were designed and built to propel a two-ton car. A fully-loaded Tesla Semi will weigh twenty times that much. What happens if you've got 43,000 pounds of canned goods in the box, you're halfway up some of America's more entertaining roads - like I-77 in West Virginia, anything in Colorado or Snoqualmie Pass in Washington - and all four of those motors fail? I suspect the fine technicians at Jane Lew Truck Stop in Jane Lew, WV, will not have four new Tesla motors in stock to get you back on the road. Oh, don't get me wrong: they could definitely get the motors into the truck. Replacing a starter would be more difficult and they do that frequently. Problem is, it's going to take Tesla a few days to get you four motors and you're going to have an extremely embarrassing conversation with your dispatcher begging him to do a power unit swap on your load so the grocery DC's manager won't kill you when you finally show up. The rest of the truck manufacturers are buying an electrification package from Bosch that comes with an industrial-grade motor.