Travel Trailer Hitches and Hitch Ratings
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How To Tow Anything! typography
Ford F-150
How To Tow Anything! typography
Travel Trailer Hitches and Hitch Ratings
Understanding the differences between weight-carrying and weight-distributing hitches — and how to correctly install a weight-distributing system
By Chris Hemer / Photos by author
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oday, there are more RV choices than ever — from well-equipped, versatile truck campers and vans to luxurious diesel pusher motorhomes costing more than a million dollars. It’s safe to say that there is truly something for everyone out there, but the most popular RV choice remains the travel trailer. It’s understandable: An outdoor enthusiast can buy one with “the basic necessities” for less than five figures or opt for every conceivable amenity — from slide out rooms and island kitchens to flat-screen televisions, theater seating and fireplaces — when using the proper tow vehicle.

Before you set out to find the perfect travel trailer for your needs, however, it’s important to understand the key component in towing: the hitch system. Let’s take a look at the various types of hitches, and how to set them up the right way.

Class is in Session
Part and parcel to a towing system is the hitch receiver — a tubular steel box located underneath the bumper that is attached to the frame or subframe of the tow vehicle. If your tow vehicle doesn’t have one, that doesn’t mean it wasn’t intended for towing; some models are only equipped with a hitch receiver if an available tow package was specified, while other small SUVs or crossovers may offer a hitch receiver as an accessory at the time of purchase. That being the case, the appropriate hitch receiver can often be added by the dealer or qualified towing/RV center, but check with the vehicle manufacturer to make sure that adding a hitch receiver to your vehicle is approved and is safe. Some vehicles don’t have adequate structure underneath to which a hitch receiver can be attached, or the vehicle’s suspension and drivetrain may not be up to the task of towing thousands of additional pounds.

That being said, hitch receivers are categorized in classes, with the smallest, light-duty receivers categorized Class I and the largest and strongest rated Class V. Looking at the accompanying chart, you’ll note that smaller, lighter receivers are designated weight carrying, meaning all of the trailer’s hitch weight (also known as “tongue weight”) is carried by the hitch itself. The larger hitch receivers (Class III and up) can either be used as weight carrying or weight distributing, meaning they are intended to be used with spring bars (or “draw bars”) to distribute some of the trailer’s hitch weight to the front of the vehicle and to the trailer axle(s).

To visualize how a weight-distributing hitch works, consider that the car/truck/SUV and the trailer are two separate vehicles that are joined together via the hitch. The spring/hitch bars in a weight-distributing hitch platform function like a “bridge” between the two that effectively distributes weight from the trailer A-frame coupler across the tow vehicle’s frame to its front axle and to the trailer axle(s), hence the term “weight distributing.” The ball mount is equipped with sockets into which one end of the bars are inserted, while the other ends attach to the trailer’s A-frame typically via chains, but not in all designs. The bars can be adjusted upwards to increase tension, or downwards, to reduce it. In this way, the appropriate amount of tension can be created to keep the trailer and tow vehicle level when hitched up. An adjustable ball mount allows the user to modify the ball height, which is important if the tow vehicle is higher or lower than the trailer’s hitch coupler. Got all that?

Measuring
hitch coupler
(TOP) The first step is to measure the trailer frame height. Kevin begins by measuring the frame between the wheels, as this is the most level part of the frame. (BOTTOM) From there, he continues forward to the hitch coupler. As you can see here, the frame height between the wheels is 23 inches, but the coupler on the same frame rail is about 20-1/2 inches. So, the trailer is raised until the hitch coupler is also at 23 inches, ensuring the trailer is completely level. If your trailer has a dropped A-frame, use the forward most part of the same frame rail for level measurement.
SuperHitch receiver
This older Ford F-350 was fitted with a SuperHitch receiver from Torklift, which is equipped with two receivers. Because of the truck’s height, the ball mount is inserted into the lower receiver and the hitch pin installed. Note that the ball mount can be installed up or down and offers multiple mounting holes to achieve the correct hitch height. If you don’t have enough drop, longer drop bars are available.
When correctly adjusted, the tow vehicle will no longer be “nose up” because the weight has been effectively distributed. Achieving a level ride height on the tow vehicle/trailer is important for several reasons: it improves steering and control, reduces fuel consumption and prevents your headlights from pointing upwards (which can blind, or at least aggravate, other drivers at night). A good RV dealer or service center should be able to correctly install and adjust your hitch the first time, after which adjustment shouldn’t be required again unless additional weight is added to the trailer or tow vehicle, or you tow more than one trailer.

As you’ve likely surmised, there are more than a few weight-distributing hitch designs on the market. A traditional “trunnion” hitch incorporates square, solid-steel bars that taper at the trailer’s end. Other systems incorporate tubes instead of bars, which may be inserted on the bottom (typical) or top of the ball mount. At least one other design does away with bars altogether in favor chains that are tightened or loosened to increase tension. When shopping for a hitch system, keep in mind that they are rated for the gross trailer weight as well as the hitch weight, so it’s important to know these figures ahead of time. We’ve provided a comprehensive guide to hitches and hitch accessories elsewhere in this issue.

Ball mount
Based on the trailer’s level height, the ball mount is inserted into the fourth hole down. It can also be pivoted up or down for nearly infinite adjustment. Once the correct hitch ball height has been achieved, the ball mount is tightened to spec.
grease application
Before hitching, it is important to apply a film of grease not only to the hitch ball, but the draw bar sockets as well. Hitch ball grease is available at RV and trailer supply stores and online. 3-IN-ONE makes a new spray version for a much cleaner and easier application.
Spring bars on truck
The truck is moved to the trailer, and the spring bars installed into the sockets. Integrated pins hold the bars in place on certain models.
icon
There are two sizes of hitch balls commonly used with travel trailers – 2-inch (usually on lighter-weight trailers) and 2-5/16 inch. The hitch ball size and capacity required for the trailer will be stamped on the trailer’s A-frame coupler so you’ll know which ball will be required. Also make sure you get the right shank diameter and length to match the bar.
To demonstrate how to correctly set up a hitch for the first time, we visited Curtis Trailers in Beaverton, Oregon. Curtis Trailers has been in the towable business since 1948, and in addition to its location in Beaverton, has another dealership in Portland. The company offers all types of towables (and truck campers) and regularly sets up new customers with hitch systems, so we took the opportunity to observe as its technician Kevin Lano installed an Eaz-Lift Elite round bar weight-distributing hitch system (part number 48057). This hitch is rated for a gross trailer weight of 10,000 pounds and a hitch weight of up to 800 pounds. The kit includes a sway control (another subject discussed elsewhere in this issue) and comes with the U-bolts and chain package already installed, as well as a 2-5/16-inch ball torqued to specification.

Installation for a professional takes less than an hour, but if you’re doing the job yourself, take your time and make sure you do it right. With a properly set-up weight distributing hitch, you’ll enjoy stable handling and remove the stress from your travel trailer towing experience.

Safe Disconnect
When you arrive at your destination, you’ll probably want to disconnect the tow vehicle and trailer so you can explore your surroundings or run errands. As with hitching up, it’s important to know how to safely disconnect the trailer. Begin by reversing the hitching procedure: unplug the power cord, then disconnect the sway control, safety chains and breakaway. Block the trailer’s tires so that it can’t move as you take the next steps.

If your trailer A-frame jack post doesn’t have a foot (there are aftermarket jack foots available), place one or more wooden blocks underneath the jack post. Raise the A-frame jack until you can grab the hitch/spring bar chains and wiggle them — this is the best way to ensure there is no longer tension on the chains. Then — and only then — can you use the lift bars to lower the saddles and release the draw bars. From there, disconnect the draw bars and stow them in a cargo compartment or a storage solution like the Hitchport. Lower the jack back down until all of the trailer’s weight is back on the hitch ball, with the jack post just off the ground. Remove the safety pin and unlatch the coupler, then begin raising the jack until the coupler is clear of the ball. If it doesn’t want to release, try getting in the tow vehicle and simply put it in neutral — this should release any fore/aft tension on the hitch ball. Once the coupler is free of the hitch ball, raise the trailer until there is adequate clearance between the ball and coupler (a couple of inches should be fine). Pull the tow vehicle forward and you’re free to go!

End of the spring bars
The other end of the spring bars connect to saddles, which locate on the trailer’s A-frame, usually behind the LP-gas cylinders. They will be clamped in place once the installation is complete, but for now they are left loose so they may be adjusted forward or back for correct chain alignment.
Raise the jack
lowered onto the hitch ball
(TOP) Raise the jack so that there is adequate clearance between the coupler and hitch ball, then back the tow vehicle up until the hitch ball is directly underneath the coupler. (BOTTOM) The trailer is lowered onto the hitch ball, and the latch locked in place. Then, the truck and trailer are raised several inches so there will be no tension on the bars during installation. It’s okay for the jack to lift both the truck and trailer far enough to attach the spring bars without strain or effort.
Receiver Classes at a Glance
Class I: Weight carrying, rated up to 2,000 pounds gross trailer weight (GTW) with a maximum hitch weight of 200 pounds. A Class I hitch usually has a 1-1/4-inch square receiver opening.

Class II: Weight carrying, rated up to 3,500 pounds GTW with a maximum hitch weight of 300 pounds. A Class II hitch usually has a 1-1/4-inch square receiver opening.

Class III: Can be weight carrying or weight distributing, depending on the vehicle and hitch specifications (not all models are designed to be both). Weight-carrying designs are rated up to 6,000 pounds GTW with a maximum hitch weight of 600 pounds. Weight-distributing designs in this category are rated up to 10,000 pounds GTW with a maximum hitch weight of 1,000 pounds. A Class III receiver usually has a 2-inch square receiver opening.

Class IV: Can be weight carrying or weight distributing, depending on the vehicle and hitch specifications (not all models are designed to be both). Weight-carrying Class IV designs are rated up to 10,000 pounds GTW with a maximum hitch weight of 1,000 pounds. Weight-distributing designs for the class are rated up to 14,000 pounds GTW with a maximum hitch weight of 1,400 pounds. A Class IV receiver usually has a 2-inch square receiver opening.

Class V: These are weight carrying and weight distributing, depending on the vehicle and hitch specifications. Weight-carrying Class V designs are rated up to 12,000 pounds GTW with a maximum hitch weight of 1,200 pounds. Weight distributing designs are rated up to 17,000 pounds GTW with a maximum hitch weight of 1,700 pounds. A Class V hitch has a 2-1/2-inch square opening. Note that the ball mount and the hitch ball itself both need to be rated for this hitch class in order to safely handle the load.

NOTE: Some of the receivers listed above have the same size opening but are rated differently. When in doubt, take a closer look at the receiver; it should have a stamp or label on it that details its capacity(ies).

Lift the spring bar chains
Lift the spring bar chains and count the number of links until you find the one that lines up with the tab on the saddle. If you find you are between links, use the lower of the two if possible. Make sure you measure the same number of links on the other side.
With the correct link
chains at this point
With the correct link placed over the tab on the saddle, the included lift bar is used to leverage the chains up. Keep lifting until the bar is vertical and the saddle snaps into place. There is very little tension on the chains at this point, so this should be easy. Once the saddle is in place, insert the safety pin so that it can’t snap back down.
trailer is lowered
Now, the trailer is lowered until the jack is off the ground. Note the position of the spring bars — they are level with the frame and are beginning to bend upwards slightly under tension. It is very important that you NEVER try to release the chains while they are under tension — the lift bar can snap down suddenly and cause serious injury. Always lift the trailer to remove tension on the chains before lowering them.
Chains and saddles
With the chains and saddles in a satisfactory position, the saddles are clamped into place on the trailer’s A-frame.
sway control
Now it’s time to install the sway control. One end locates on the small ball on the ball mount, the other end to a bracket on the frame. Eaz-Lift provides instructions on how to measure and mount the sway control bracket; this one was installed prior to the hitch set-up.
Pins are installed on truck
Sway control so they don’t come off
Pins are installed at either end of the sway control so they don’t come off of their respective balls.
Sway control friction
Sway control friction is adjusted with this lever. Lift it with just one finger until it stops as an initial adjustment; it can be lifted farther for more friction if additional sway control is required. Eaz-Lift notes that two sway controls (one on each side of the trailer A-frame) may be required for larger/longer trailers. City and campground driving with sharp turns must be avoided while the bars are attached to avoid damage.
Attach the trailer’s safety chains
Attach the breakaway cable
(TOP) Attach the trailer’s safety chains to the eyes in the hitch receiver. (BOTTOM) Attach the breakaway cable to the hitch receiver. The breakaway is a safety device that applies the trailer’s brakes should it become disconnected from the tow vehicle.
Plug the trailer’s power cord
Plug the trailer’s power cord into the receptacle on the truck. To prevent the cord from hanging down, trap it inside the hitch ball latch pin, as shown. That’s it — you’re now good to go. RVE.
Sources:
Curtis Trailers
(503) 743-6758
(Beaverton, OR)
curtistrailers.com

Eaz-Lift
(800) 334-2004
eaz-lift.com