Buying Your First Freightliner? 4 Types of Rigs & Valuable Trailer Hook-Up Info to Consider

You've had that dream about a life on the road and finally decided to turn that ever-present wish into reality. Before you invest in that semi-truck, consider what types of hauling you'd like to do. Do you want to invest in your own trailer or just buy the tractor so you can haul various company rigs? Are you planning on being home most nights, or wanting to do long hauls that can last days, or weeks?

Getting a freightliner truck for sale is also a consideration. Below are descriptions of four types of semi-trucks, followed by some helpful information on those all important trailer connections.

Four Basic Types of Semi-Trucks

Semi-trucks are actually two separate vehicles hooked together. The tractor, often referred to as the truck, houses the engine and driver's compartment. The trailer that carries the merchandise. Most semi-trucks in the trucking industry fit into four basic categories.

1. Rigs Designed for Long Haul Drivers: The tractors on semi-trucks used for long haul trucking typically have sleepers just behind the cab. Drivers on these routes are often gone for days or weeks at a time and that tractor is their home away from home. These rigs can pull an assortment of trailers, such as closed boxes used for dry goods, refrigerated units, flatbeds or tankers.

2. Rigs for Short Haul Trucking Routes: Local haul semi-trucks may or may not have a sleeper. Some local routes can cover adjacent cities, others may span out over entire states. Drivers may or may not make it home every night. These semi-trucks tend to have shorter wheelbases and trailers to allow for easier driving in city situations.

3. Rigs for the Heavy Haulers: Drivers in the heavy hauling industry are responsible for moving large items such as cranes, oil field or general construction equipment. Much of this hauling is done on trailers that have low decks to make it easier for loading and unloading. The lower center of gravity also makes the semi-truck combination more maneuverable. The cabs on these rigs may or may not have sleepers.

4. Rigs for Those Specialty Hauls: Some semi-trucks are designed for one purpose and trucks and trailers are usually purchased together. Exceptions would be if either the truck or trailer sections needed replaced with like units. The car hauler is one example of a specialty rig. The tractor is modified to fit a specific trailer. That trailer is a mobile skeleton that protects vehicles in transit. Larger car haulers often carry vehicles over the cabs of the trucks. Ramps pull out of the back to allow the cars or trucks to be loaded and unloaded.

Making the Connection

If you are buying your own rig, chances are you have some experience in driving some sort of large truck. If that time was spent time in trucks that have the "hauling end" permanently attached, you'll appreciate the versatility of changeable trailers. For example, instead of making a delivery and waiting until your truck is unloaded before hitting the road, it's just a matter of dropping the trailer and hooking up the next one. 

Two devices, the fifth-wheel and the kingpin, connect the trailer with the tractor, making the switching of trailers possible. The connection acts as a pivot point between the two halves of the rig, making turns easier and increasing stability.

The fifth-wheel sits on the back of the tractor. It is a large metal disk with a "V" shaped notch facing backwards. It has a lock inside to hold the trailer's kingpin.

The kingpin is a long metal piece of steel surrounded by its own metal grid plate. When the tractor is backed up to the trailer, the two plates slide against each other and the kingpin drops in the "V" slot.

The "landing gear" on the front of the trailer is rolled up. Landing gear, typically made of a heavy duty frame and metal wheels, supports the front of the trailer when standing alone.  Electrical and brake connections are plugged in. Your rig is ready to roll.