Although he didn't specifically state September's electric semi-trailer will be a concept, there's a high chance that will be the case, given the startup car maker will have its hands full getting the Model 3 into mass production and has no production facilities capable of building a freight-hauling truck.
Responding to feedback, Musk also confirmed an electric pickup truck or ute will be unveiled within "18 to 24 months".
Last year, when he unveiled Tesla's latest grand plan, Musk said the Model 3 would be followed by a related crossover and a “new kind of pickup truck”.
He also said that Tesla should enter the bus and heavy-duty truck markets, although he gave no timeline for these products.
Two weeks ago, on the back of strong production and sales in the first quarter, Tesla's market capitalisation overtook that of Ford. A week later, the electric automaker briefly overtook GM in that same metric.
At the time of writing, Tesla's shares are worth US$304 ($405), valuing the company at US$49.6 billion ($66 billion). That puts it well ahead of Ford's capitalisation of US$44.2 billion ($58.8 billion), but just behind GM's US$50.3 billion ($66.9 billion).
Last year, Tesla made a total of 83,922 cars, while Ford sold 6.6 million vehicles globally, and GM managed to sell just shy of 10 million cars and trucks.