Tow Hitches and Weight Ratings 

From Jim Walczak,
Your Guide to 4-Wheel Drive / Offroading.

(GVWR) Gross Vehicle Weight Rating

This is the maximum amount of weight that a given vehicle can weigh - including its passengers, fuel and cargo - without being overloaded.

(GCWR) Gross Combined Weight Rating

The maximum a vehicle plus its trailer - including cargo, fuel, and passengers - can weigh without being overloaded.

(GAWR) Gross Axle Weight Rating

The maximum weight an axle is rated to carry. It includes the weight of the axle.

Tow Rating

The manufacturer's figure for the maximum trailer weight a vehicle is rated to tow.

Axle Weight

The weight of an individual tow vehicle's axle, or the weight of a trailer's axle (or axles), but does not include the trailer's tongue weight

Weight
This is the maximum weight of your (fully loaded) trailer that your truck can tow.

Tonnage Weight
The amount of weight that pushes down on the trailer hitch.

Tow Weight
This is a rating by the manufacturer for how much combined weight the truck can pull with a loaded trailer. (tonnage weight and GCVR)

If you have any doubts about the weight of your load, there are public scales used by truck drivers located at most truck stops. Be sure to have your loaded vehicle weighed before you begin your trip.

Hitches are rated as follows:
C= Class
GTW=Gross Trailer Weight

TW=Tongue Weight

C=I
GTW =up to 2,000 lbs
TW =up to 200 lbs

C=II
GTW =up to 3,500 lbs
TW =up to 300 lbs

C=III
GTW = up to 5,000 lbs
TW =up to 500 lbs

C=IV
GTW =up to 10,000 lbs
TW =up to 1,000 lbs

There are two types of hitches: weight carrying and weight distributing.

Weight Carrying hitches:
These hitches attach to the frame of the towing vehicle and provide a connection point between the towing vehicle and whatever you are towing. Weight carrying hitches support all of the trailer tongue weight so they are best suited for small to medium sized loads.

Weight Distributing hitches:
These hitches are recommended for heavier trailers. Weight distributing hitches will even out the trailer load between the wheels of the tow vehicle and the wheels of the trailer. You will experience improved steering and brake control.

Bumper Hitches

The bumper/frame hitch is also good for light towing, however it has one serious drawback: It tends to reduce the energy-absorbing benefits of most modern bumpers.

The step bumper also relies on solid attachment points on the frame. Beware of aftermarket step bumpers that have no frame attachment points.

Another undesirable hitch is the bumper-mount hitch. Most automotive manufacturers do not recommend using this hitch, because modern bumpers aren't designed for towing.

Receiver Hitches
The ball mount (also called ball platform) is removable when the hitch is not being used. This leaves the hitch's opening about even with your bumper.
The most popular style of hitch and is what you see on most trucks, SUV's, RV's and vans.

Best choice when using bike racks, ski racks, cargo racks.
Available with two size openings, 1 1/4" and 2".

Class I and II receiver style hitches can only be used for towing as a weight carrying hitch.

Class III and IV receiver style hitches can be used either as a weight carrying hitch or as a weight distributing hitch when a weight distribution system is added.

Receivers can also be installed on the front of your vehicle to make launching and recovering boats easier, to attach bike racks while you are towing a trailer or to mount a winch.

Gooseneck Hitches / 5th Wheel Hitches

Fifth Wheel Hitches and Gooseneck Hitches are special hitches mounted through the bed of your truck to brackets or the vehicle's frame.