Trailer Hitch Parts

Hitch Receiver Mounted to Pickup Truck

What You'll Need to Install a Receiver Trailer Hitch

Trailer hitches are rated a couple of different ways:

• by how much weight they can tow, and
• by their maximum tongue weight (the weight applied downward on the hitch ball)

Hitch Classes

• Class I - up to 2,000 pounds gross trailer weight, 200 pounds maximum tongue weight
• Class II - up to 3,500 pounds gross trailer weight, 350 pounds maximum tongue weight
• Class III - up to 5,000 pounds gross trailer weight, 500 pounds maximum tongue weight
• Class IV - up to 12,000 pounds gross trailer weight, 1,200 pounds maximum tongue weight

Gooseneck and fifth-wheel hitches can tow considerably more, but the weight you can safely tow depends on your truck's towing capacity.

Trailer Hitch Parts

This type of trailer hitch has a receiver that mounts to the truck frame (most of the receiver is hidden by the rear bumper). The square hole that's visible in the receiver is where the draw bar, the piece the hitch ball is bolted to, is inserted.

Draw Bar Installed in Receiver Hitch

Trailer Hitch Parts

The draw bar slides into the receiver's square hole and a pin is inserted through the side, moving thru the hitch and the bar to hold the bar securely in place. One of the benefits of a receiver style trailer hitch is the option to remove the draw bar when the hitch isn't being used, in order to eliminate the extra length it occupies at the rear of the truck.

Two Different Slide-in Draw Bars

Trailer Hitch Parts

Imagine a line that flows from the hole in each draw bar towards the ball on its end, and you'll see that the ball on the left bar sits lower than the ball on the right bar. Draw bars are made in many configurations -- this photo shows just two examples. Evaluate the height of your vehicle and choose a bar that puts the trailer tongue as close to level as possible.

On the right is the pin that passes through the draw bar and into the receiver hitch, along with the clip that hooks around the end of the pin to hold it in place. Some pins lock in place with a key to help prevent theft.

Hitch balls are available in several different sizes, so make sure the ball you choose matches the size required for your trailer.

There are also two different hole/thread sizes where the ball attaches to the draw bar. Check that specification when choosing hitch equipment.

Example of a Ball Mount on a Trailer Tongue

Trailer Hitch Parts

There are many different configurations for trailer tongues. Pay close attention to the ball mount at the end of the tongue, which fits over the trailer ball. The ball on the hitch and the mount on the tongue must be the same size for the system to lock securely in place.

Plug-in on Truck for 7-Pin Connector

Trailer Hitch Parts

Trailer wiring connectors come in many configurations. This photo illustrates one design for a 7-pin connector, the type of connector normally used in trailers equipped with electric brakes and/or additional lighting.

Plug-in on Truck for 4-Pin Connector

Trailer Hitch Parts

Four-pin wiring connectors are used in most utility trailers and small boat trailers.

Typical 4-Pin Wiring Plug on Trailer

Trailer Hitch Parts

Here's the wiring on the trailer that slips into a 4-pin connector on the truck.

Dodge Ram Heavy Duty Gooseneck Trailer Hitch

Chrysler offers a Mopar gooseneck trailer hitch for Dodge Ram heavy duty trucks from model years 2005 or 2006 onwards, depending on which body style you own. It takes about an hour to mount the hitch in the bed -- expect to do some drilling but there's no welding involved. The unit is compatible with factory and BedRug bedliners and a quick-release handle lets you remove the ball when you need a flat floor. Expect to spend about $450 for the hitch and a separate installation kit -- more if you don't install it yourself.

Fifth Wheel Hitch in Tundra Diesel Dually Project Truck

The Tundra Diesel Dually is a custom truck built for show. Its diamond plate-lined bed holds a Reese fifth-wheel trailer hitch that's rated at 24,000 pounds.