TWheels: Trailers

Eric Meltzer
Apr 17, 2018 Updated 16 hrs ago



It’s trailer season. Spring brings out the smallest utility trailer to the largest boat trailer, with every conceivable camper trailer in between. Driving forward with a trailer in tow is quickly mastered but backing up is the bane of many a trailer hauler.

Before we jump ahead, let’s cover some basics first, and we’ll focus on towing using a car or light truck, leaving the heavy hauling to the commercial drivers out there.

Towing, by definition, requires a tow vehicle and trailer. Between these units is the hitch that mounts to the tow vehicle. Inserted or mounted to the hitch is the draw bar or ball mount to which, just like the name implies, the hitch ball is mounted.


The draw bar is secured to the hitch with a hitch pin and clip. Creative names apparently have no place in towing. On the trailer side, the coupler secures to the hitch ball on the tow vehicle; safety chains act as a secondary security feature and hook to the tow vehicle from the traile;, and finally, the wiring “pig tail” plugs into the tow vehicle powering the trailer lights and other electrical accessories.

There are five trailer hitch classifications, but we’ll focus on Class 1, 2 and 3 (you’ll also see the class numbers depicted as Roman numerals). Each class represents a weight limit. Trailers have two significant weight ratings; overall or gross weight and tongue weight.

A Class 1 hitch can tow up to 2,000 pounds with a 200-pound tongue weight; Class 2 can handle 3,500-6,000 pounds with a 350-600-pound tongue weight; Class 3 can haul a 10,000-pound or 5-ton gross trailer weight or 1,000-pound tongue weight.

Class 1 and 2 hitches are usually made up of 1¼-inch square tube receivers, while Class 3 hitches are generally 2-inch square tube receivers. It’s important to understand that the hitch class defines the towing capacity. A 2-inch receiver bolted to a bumper is not a Class 3 hitch, regardless of the size draw bar that hitch will accept.

The old pickup truck-style step and tow bumper had no receiver; instead, the ball was bolted directly to the bumper. But the towing capacity was defined by the manufacturer and was dependent on materials, construction and mounting configuration. A square tube receiver is sometimes referred to as a “Reese” hitch; however, that is the name of a manufacturer that popularized receiver hitches and not an actual type of hitch.

In addition to receiver hitches, there are also fixed draw bar, bumper mounted like the previously mentioned step and tow, weight distributing that are similar to a Class 3 but allow an increase in weight and towing stabilization, pintle hitches — like interlocking rings — commonly used in construction and military applications, gooseneck hitches that mount to the bed of a truck but use a ball, and fifth wheel hitches like those used by tractor-trailer trucks where the coupler is part of the hitch and a pin or ball is mounted to the trailer.

The hitch ball and coupler sizes must match. Common hitch ball sizes are 1 7/8, 2 and 2 5/16 inches. (They seem like random sizes to me, too.) 

Similar to towing capacities, the hitch ball generally equates to weight ratings, with larger balls required for heavier trailer couplers. Size matters. A 2-inch coupler will fit on a 1 7/8-inch ball, but it’s not correct and it is unsafe. Yes, the trailer will depart the tow vehicle under certain circumstances when a smaller ball is used under a larger coupler. It happened to a friend. Really. No, it wasn’t me.

Receiver hitches have gained in popularity for use with accessory carriers. Plug in a bike rack or luggage carrier and instantly increase your vehicle’s cargo capacity. 

Be aware, however, that anything you mount behind your vehicle will stick out beyond most other drivers’ expectations and can also pose a hazard by blocking taillights, brake lights and license plates.

Check with states you plan to travel through when using such a device to be sure you’re in compliance with their roadway laws.


Frequent towing or towing heavy loads requires more than just a hitch mounted to the tow vehicle. 

Many trucks and SUV manufacturers offer towing packages from the factory. These include heavier springs and shocks, larger brakes, transmission fluid coolers, variable transmission shift points and factory-installed hitches and trailer wiring that may accommodate trailer brakes.

Trailers should sit level when loaded and hooked to the tow vehicle. Drop hitches and drop draw bars are available to keep the geometry consistent. 

An improperly loaded trailer or incorrectly matched unit can become problematic when hauling. Issues such as lack of traction, light or loose steering, and trailer sway can quickly become dangerous conditions at faster speeds.

Trailers do require some maintenance, especially after sitting for extended periods of time. Tires should be checked for dry cracking, rotting and proper inflation, lights should be connected and verified to ensure correct function. 

Faulty grounds from corrosion and blown bulbs are common issues with trailer electrical components. Wheel bearings should be checked regularly for appropriate lubrication and play and should be repacked and adjusted when necessary. Overall checks of springs, welds and structural integrity should be performed regularly as well.

Hauling a trailer is a specialized niche and should be handled with care and caution. Next week, we’ll discuss hooking up and towing.

Eric and Michelle Meltzer own and operate Fryeburg Motors, a licensed, full-service automotive sales and service facility at 299 Main St. in Fryeburg, Maine. More than a business, cars are a passion, and they appreciate anything that drives, rides, floats or flies.

 In 1971 J. Standard Baker Quoted " Drivers Towing Trailers  Are Four (4) Times As Unsafe As Those In Cars Alone!