The three most common pieces of loading dock equipment for unloading a trailer are the pit style Dock Leveler, the Dock Lift, and the Edge of Dock Leveler. Each unit operates differently from the others, and I’ll explain all three below.

Dock Leveler

The most common and most ergonomic piece of loading dock equipment is the traditional Dock Leveler. Essentially it does just what its name implies, levels the dock for the transition of materials into or out of a tractor trailer.

Not all trucks are designed the same. Over the last few decades, the industry has established 48″ as the standard loading dock wall height for most loading dock applications. The reason for this is that most over the road tractor trailers have a bed height of 48″. That means transitioning goods from the truck to the loading dock area is done on a fairly level grade. However, not all truck bed heights are designed the same.

For example, a container truck has standard bed height of 56″ – 62″. For this reason, dock levelers come with the ability to operate 12″ above, and 12″ below grade. That means a dock leveler installed on a 48″ high dock wall, can accommodate trucks with bed heights ranging from 36″ to 60″ (12″ above and below the 48″ high wall). That means a dock installed at this height can accommodate almost all trailers shown in the table below.

Forklift Dock Leveler Trailer

A forklift uses a Dock Leveler to transition goods from the warehouse loading dock floor to the van of a semi-trailer. Picture by Blue Giant Dock Equipment

If your company services trucks that are routinely above or more likely below the standard 48″ height, then you will want to install a different height dock wall to accommodate your specific application.

Pro Tip: Choose a proper middle ground to make sure you can service a variety of trailers. For example, if you commonly service Furniture Van’s (24″ min. bed height), install your wall and dock leveler at a 36″ height so you can service a 24″ Furniture van, as well as a 48″ Straight Truck. Remember, most dock levelers can operate 12″ above and 12″ below the installed height.

Trailer Type Min. Truck Bed Height Max Truck Bed Height Min. Overall Truck Height Max Overall Truck Height
Container 56″ 62″ 12’2″ 13’6″
Reefer 50″ 62″ 12’6″ 13’6″
Double Axle 44″ 52″ 12’0″ 13’6″
City Delivery 44″ 48″ 11’0″ 12’6″
High Cube Van 36″ 42″ 13’0″ 13’6″
Furniture Van 24″ 36″ 13’0″ 13’6″
Step Van 20″ 30″ 8’6″ 10’0″
Panel Truck 20″ 24″ 8’0″ 9’0″
Straight Truck 36″ 48″ 10’6″ 12’0″
Flatbeds 48″ 60″

McGuire Loading Dock Equipment has put together this short video to show how simple it is to operate a Hydraulic Dock Leveler. Essentially, one will push a button to raise the leveler and extend the lip, and allow the leveler to lower onto the semi-trailer for transition of goods. Once the goods have been transferred, the operator will once again engage the button which will raise the leveler up, lower the lip back to it’s resting position, and allow the dock to return to it’s resting state and the tractor trailer driver to depart the loading dock.