While overall truck sales have taken a pause, Ford reports that its larger F-650 and F-750 models are still firing on all cylinders. Sales from January through August were up 59%, to 10,160 units, since last year. The company calls these results for Class 6-7 trucks its best since 1997.

Volumes of such trucks are relatively small compared to pickups or Class-8 rigs, but they are important construction vehicles that provide a wide range of movement for materials, equipment and other items that require more capability than a lighter Super Duty but may not be a good fit for heavy-duty trucks.

Some manufacturers have left this market in favor of investing in higher-volume trucks. For example, pickups have risen, notably in their towing and hauling numbers. This hike has left space open for other truck makers to expand the medium-duty class.

Ford’s legacy F-650/750 was getting long in the tooth, so last year it invested $168 million in its Avon Lake, Ohio, assembly plant to move production from Mexico while upgrading ride quality, switching to a new automatic transmission and offering the only gasoline engine in the class. The 6.8-liter V10 also can be converted to run on natural gas. A 6.7-liter Power Stroke V8 turbodiesel offers even more firepower while cutting cab noise by 45%.