Ford F-150 Lightning prices are going up again. The US automaker is raising the electric pickup’s starting cost by $4,000, bringing the new entry price to $55,974. That’s a 40 percent increase over the electric vehicle’s initial starting price in May 2021.

Ford toldCNBC today that it is changing pricing “as a normal course of business due to rising material costs, market factors, and ongoing supply chain constraints.” Raw material costs of nickel, cobalt and lithium — crucial to electric car batteries — have soared alongside EV demand.

Through the end of November, Ford has only sold 13,258 F-150 Lightning units, but that number is a reflection of supply constraints rather than low demand (on the contrary, the truck is still a hot commodity). The company plans to boost production to 150,000 units by next fall — and it said earlier this week that it’s still on track to meet that goal. It recently added a third shift of workers to a Michigan production plant to help meet that goal.

Ford is the second-biggest American seller of electric vehicles (behind Tesla), and the F-150 Lightning is the top-selling electric truck. Considering Ford F-series trucks have been the best-selling vehicles in the US for three decades, that customer loyalty appears to be carrying over to EVs. Earlier this year, Engadget’s Roberto Baldwin rode along for a test drive and commented on how much it felt like a standard F-150.