See Inside Mack's New Next-Gen Keystone Semi-Truck
Mack has unveiled an all-new Keystone semi-truck model to sit alongside its existing models like the long-haul Pioneer and regional-haul Anthem. The manufacturer says that the Keystone is designed to be one of its most versatile models to date, tackling both unpaved roads and long highway hauls without the compromises that are usually associated with prioritizing one type of terrain over the other. It's designed to succeed the Pinnacle, which has been part of the brand's lineup for over two decades. To differentiate it from the rest of the lineup, Mack has given the Keystone additional ground clearance and an all-terrain suspension, as well as improving its approach angle.
Drivers with experience of the latest Pioneer should find the interior of the Keystone familiar, since the two models share the same basic features and layout. However, the Keystone's cabin isn't identical to the Pioneer's, with Mack adding new features, including a flat-bottomed steering wheel that's designed to make long hauls more comfortable for larger drivers. The interior also features several unique touches with design elements that pay homage to the classic Mack R Model.
Carried over from other contemporary Mack models are the seats, electronic braking system, and wrap-around controls. While the brand includes all the essential features as standard, extras, including a digital mirror system, are available as options.
The Keystone offers Mack's integrated powertrain
Separating Mack from other semi-truck manufacturers is its integrated powertrain, which is offered as standard with every example of the Keystone. The brand's MP13 engine is the sole engine option, while the mDRIVE HD automated manual transmission handles shifting. 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 of the key components communicate with each other as efficiently as possible, and to maximise 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 issues with the truck, as well as letting owners monitor vehicles in real time.
The Keystone will be available as both a day cab and a sleeper, with the latter option available in 44-inch and 64-inch configurations. Multiple rear axle configurations are also available to suit a wide variety of buyer needs, with Mack positioning the truck to target a range of industries, including everything from construction and logging to livestock hauling. A new modular bumper lets owners configure their ideal towing setup without compromising on styling. Buyers can expect order books for the Keystone to open in the second half of 2026, although an exact date hasn't yet been announced at the time of writing. Mack has confirmed that the model will be available in North America and in some Latin American markets.