I know Elon has stated something like MadMax designed pickup is coming, but I wander if he is misdirecting a bit too. Would not surprise me if during the Y reveal he reveals a unibody truck based on the Y/3 platform.
While a HD pickup truck based on the Semi looks cool, unless it sells in high volume it will not pay the bills. A unibody pickup (like the Honda Ridgeline, and new unibodies that Ford and Hyundai are working on) based on proven mechanicals would be a slam dunk sales wise for Tesla. Tesla needs slam dunks more than "cool".