Elon Musk promises the cargo hauler is "seriously next level."

Tesla CEO Elon Musk has confirmed plans to unveil an all-electric semi truck in September, followed by a pickup truck in 18-24 months.

"Team has done an amazing job," he wrote in a Twitter post, referring to the semi. "Seriously next level."

The executive did not divulge more details, though the heavy-duty cargo trucks could mesh with Tesla's vision for other working vehicles. The company is also working on high-passenger-density urban transport in which the role of bus driver transitions to that of a "fleet manager."

A truck capable of operating with SAE Level 4 autonomy could allow the driver to rest in the cab while the vehicle drives itself on long-haul trips. The next obvious step is Level 5, which could allow Tesla's semis to haul cargo without any human driver present in the vehicle.

Tesla also envisions a driverless network of ride-hailing vehicles, allowing a customer's personal vehicle to make money on the side as an autonomous taxi while the owner is at work.

In the near term, Tesla's operations will continue to be closely watched as the company attempts to launch its important Model 3 sedan and quickly scale up production to fulfill hundreds of thousands of reservations.