See Inside Mack’s New Next-Gen Keystone Semi-Truck

Mack has introduced a new Keystone semi-truck model that will sit alongside its existing long-haul Pioneer and regional-haul Anthem models. The manufacturer says the Keystone is designed to be one of its most versatile models to date, tackling unpaved roads and long-distance traction without the compromises often associated with prioritizing one type of terrain over another. Designed to succeed Pinnacle, which has been part of the brand’s lineup for over two decades. To set it apart from the rest of the lineup, Mack gave the Keystone more ground clearance and an all-terrain suspension, as well as improving its approach angle.

Drivers familiar with the latest Pioneer should find the Keystone’s interior familiar, as the two models share the same basic features and layout. However, the Keystone’s cabin is not the same as the Pioneer’s, with Mack adding new features, including a lower steering wheel designed to make long hauls more comfortable for larger drivers. The interior also has a few unique touches with design elements that pay homage to the classic Mack R Model.

Carried over from other current Mack models are the seats, electronic braking system, and roll controls. While the brand includes all the essential features as standard, extras, including a digital mirror system, are available as options.

What sets Mack apart from other small truck manufacturers is its integrated powertrain, which is offered as standard with every Keystone example. The stock MP13 engine is the only engine option, while the mDRIVE HD automatic transmission is flexible. The MP13 can also be found in the Pioneer, and offers 540 horsepower and 1,950 lb-ft of torque in the Keystone.

A key part of the appeal of the Mack integrated powertrain is that all key components communicate as efficiently as possible, and to maximize that efficiency, the manufacturer offers a five-year subscription to its Mack Connect telematics software. Among other things, the software enables Mack technicians to remotely diagnose problems with the truck, as well as allowing owners to monitor vehicles in real time.

The Keystone will be available as a day cab and a sleeper, with the latter available in 44-inch and 64-inch configurations. Multiple rear axle configurations are also available to suit a variety of customer needs, Mack positions the truck to target a wide range of industries, including everything from construction and logging to livestock transportation. The new modular bumper allows owners to customize their aesthetic setup without compromising on style. Buyers can expect Keystone order books to open in the second quarter of 2026, although an exact date has not been announced at the time of writing. Mack confirmed that the model will be available in North America and some Latin American markets.