What Is the Difference Between a Class III & a Class IV Receiver Hitch?by Christopher Jackson
There are five classes of regular-duty, receiver-type trailer hitches, graded from I (one) to V (five) in terms of load capacity and intended use. The capacity of the hitch is as important as the towing capacity of the vehicle itself.
Receiver hitches mount below the rear bumper and are attached to the frame of the vehicle. A Class I hitch is the smallest; it's designed for use on passenger cars and is rated to tow up to 2,000 pounds. The slightly larger Class II hitch can handle up to 3,500 pounds, and can be found on small sport-utility and crossover vehicles. The hitch ball slides into a 1.25-inch "receiver" tube, hence the name.
For larger trailers, a Class III or IV hitch is recommended. The Class III hitch has a sturdier attachment and a larger, 2-inch receiver tube, and is often found on full-size pickups. It can handle up to 8,000 pounds, with 800 pounds of tongue weight.
The Class IV hitch also uses a 2-inch receiver box, but sturdier construction allows its capacity to go up to 10,000 pounds and 1,000 pounds of tongue weight. Class IV hitches are traditionally only found on heavy-duty pickups that are rated to tow that much weight.
The heavier-still 12,000-pound Class V hitch is generally found on super-sized medium-duty trucks. Trailers that go beyond this capacity are usually equipped with a fifth-wheel-type design that moves the tongue weight forward of the rear axle.