Bolk uses different types of tractor units for the various types of shipment. Tractors with 3 or 4 axles provide more load capacity. Low trailers with 2 or 3 axles used in combination with open or closed megatrailers provide additional load height. Double-drive bogies, hub reduction and torque converters increase the pulling force for dealing with heavy loads. Bolk also has crane tractors and closed box trucks with a crane or tilt system.

All the tractors are fitted with an on-board computer. The standard installation of an alcohol lock and distance radar contribute to road safety.