Hitch Basics | Select StowAway2.com

Trailer Hitch Basics

This trailer hitch overview will provide you with the basic information you will want to know when selecting a hitch for the StowAway Cargo Carrier. The following topics are covered.

  1. Hitch Capacities 
  2. Trailer Hitch Classes and Sizes
  3. StowAway Compatibility
  4. Hitch converters, hitch extenders and drop hitches 
  5. Hitch wiring kit
  6. Installing a Hitch on Your Vehicle

1) Hitch Capacities

Hitches are generally rated in two ways, towing capacity and tongue weight capacity.  Towing capacity is the gross weight (GTW) that can be towed by the hitch, either in the form of a trailer or in the form of a car. Hitch towing capacities typically range from 1,000 to 10,000 lbs depending upon the size and weight of the vehicle doing the towing. The tongue weight capacity is the maximum vertical weight that the hitch can support, and typically ranges from 100 lbs to 750 lbs. The tongue weight capacity is the most relevant hitch capacity for determining a fit for the StowAway Carrier, as the StowAway represents unsupported vertical weight. Shorter, lighter vehicles tend to have lower hitch capacities and larger, heavier vehicles tend to have higher hitch capacities. 

It is important to note that your vehicle and your hitch may be rated for different capacities.  If this is the case you must use the lower of the two to determine what you can carry or tow with your hitch.  To determine your vehicle's capacities consult with your owner's manual or your dealer. Your hitch capacities can usually be found on the hitch itself or, if it is an OEM hitch, in the vehicle's owner's manual or through the dealer. If your hitch and vehicle do not specify a tongue weight capacity, you can use the rule of thumb, 10% of towing capacity, to estimate your tongue weight capacity. So, a hitch and vehicle with a 2000 lb towing capacity will have a 200 lb tongue weight capacity. (10% of 2000 lbs). 

2) Trailer Hitch Classes and Sizes

Curt HitchHitches are commonly classed depending upon their capacities.  Class 1 hitches are the lightest duty hitches and Class V hitches are the heaviest duty hitches. The most common hitch on sedans and station wagons is a Class 1 hitch, while the most common hitch on mid to large SUV's and RV's is a Class III hitch.  


Hitch openings (inside dimension) measure either 1.25" square or 2" square, with the exception of the Class V hitch which measures 2.5" square at the opening. Class I hitches are always 1.25" square, while Class II hitches can be either 1.25" square or 2" square at the opening.  Class III and IV hitches are always 2" square. 

The following chart shows the most common hitch capacities for the different hitch classes. These are only a guide, so check your specific vehicle and hitch to determine your towing and tongue weight capacities. 

Hitch Class
Tongue Weight Capacity*
Towing Capacity*
 Class I
 100-200 lbs.
1,000-2,000 lbs.
 Class II
 250-350 lbs.
2,500-3,500 lbs.
 Class III
 350-500 lbs.
3,500-5,000 lbs.
 Class IV
 500+ lbs.
7,500-10,000 lbs.
*Approximation: Depends upon vehicle.

3) StowAway Compatibility

All StowAway carriers and racks slide directly into the trailer hitch mounted to your vehicle. StowAway carriers are designed for use with either 1.25" or 2" hitches, as long as the hitch and vehicle capacities are adhered to.  We generally do not recommend the StowAway Carrier for Class I hitches because of their low tongue weight capacity ratings, typically 100-150 lbs. 

In addition to your hitch and vehicle capacities, there are several other factors to consider when determining whether the StowAway will fit your vehicle. These include a rear mounted spare tire or ladder, the location of the hitch and the rear door/liftgate geometry when opening.  StowAway does however, offer a frame and model that will fit the vast majority of vehicles on the market, assuming the vehicle offers at least 150 tongue weight capacity. For more information see our StowAway Cargo Carrier Fit Guide

StowAway carriers and racks are rated to carry up to 200 lbs of gear with the 2" hitch model, and 125 lbs of gear with the 1.25" hitch model.  

4) Hitch Converters, Hitch Extenders and Drop Hitches

The most common hitch converter is a hitch insert that converts your hitch from a 1.25" to 2" opening. This is done so that a lighter duty 1.25" hitch can accomodate a 2" rack or carrier. Under no circumstances do we recommend the use of a hitch converter with the StowAway Carrier because it extends the hitch opening out 7", putting undue stress on an already light duty hitch receiver.    

Hitch extenders
are designed to move the hitch opening out by 7" to clear a rear mounted spare tire or ladder. Hitch extenders reduce the tongue weightHitch extender capacity of the hitch by 1/3 so this should be accounted for when using a hitch extender.  We only recommend a hitch extender for Class III and IV hitches.

Drop hitches are used to lower and extend the hitch opening on certain vehicles, generally those equipped with a spare tire and a side opening rear door. They extend the hitch opening by 6" and reduce the tongue weight capacity of the hitch by 1/3.  We only recommend a drop hitch for Class III and IV hitches.    

5) Hitch Wiring Kit

Most StowAway models are equipped with taillights which plug into an electrical connector on the vehicle. Hitches installed at the factory generally come wired with this electrical connector as standard. If you are having an aftermarket hitch installed, or are installing the hitch yourself, you must select a hitch wiring kit so that the StowAway Carrier taillights can be utilized. The StowAway wiring is equipped with a four flat connector, so you will want the corresponding connector on your vehicle or may need an adapter to plug into your connector.

6) Additonal Questions?

Contact one of our Cargo Carrier specialists via email, or call us toll free at 800.943.5377