ForConstructionPros.com

Used for everything from inflating tires to powering pneumatic tools, compressed air can be invaluable on many jobsites. It can also be invaluable if your applications allow you to mount the compressed air supply onto your mechanics truck to free up the hitch for towing other equipment, or increase mobility by eliminating the need to tow anything at all.

"You don't have to tow a portable unit to the jobsite," says Dan Kokot, vice president, Vanair. "You can use one truck to do it all and still meet all your air needs. It can improve your efficiencies."

There are numerous choices for onboard air compressors, ranging from under-hood or -deck models to above-deck units that are available in rotary screw- or reciprocating piston-type configurations driven by belts, hydraulics or PTOs.

Location, location, location

As in real estate, location can be an important consideration when determining which compressor is right for your truck.

Above-deck compressors — also known as utility skid mounts — are the most common, primarily because they're versatile. They come in a range of cfm/psi ratings, and are available in rotary screw and reciprocating piston types with hydraulic, gas or diesel drives. They are also less expensive than comparable under-hood or -deck models, and many can be moved to a new truck body if they outlive their initial host.