Ram could be planning a down-sized engine for its next pickup.

A new round of spy shots indicates Ram could be planning a four-cylinder engine option for its next-generation 1500 pickup truck model.

Our spy photographers managed to snap a few pictures of a Ram prototype with its hood up, revealing what appears to be a four-cylinder powerplant. Given the sheer size of the Ram 1500, the four-cylinder is presumed to be using turbocharging technology for extra power.

Although a four-cylinder might seem out of place in a full-size truck, CAFE regulations could force Ram (along with other manufacturers) to go down the small engine route. We've already seen that from the Ford F-150 with its range of downsized EcoBoost engines.

Believed to be related to the Hurricane turbo-four destined for the engine bay of the next-generation Jeep Wrangler, the mill in this Ram prototype likely displaces 2.0L. Thanks to technologies like direct-injection and an integrated water/air charge cooler, the four-cylinder should be good for at least 300 horsepower.

However, it's possible that Ram could pair the new four-cylinder with some kind of hybrid system, which would net extra power — and efficiency — for the big pickup.

Ram is expected to unveil its next-generation 1500 pickup truck at the 2018 North American International Auto Show in Detroit.