The tow rating is the maximum towing capacity that your tow vehicle, equipped with a towing setup and a suitable trailer, can safely tow down the road.
Understanding the tow rating of your setup is crucial, and you need to make sure that you never exceed the maximum towing capacity at any time. You, as the owner of the vehicle, are directly responsible for the decision to equip and operate your car or truck with a loaded trailer, so it is up to you to confirm if your specific towing setup is up to the task.
The maximum towing capacity of your vehicle, or its tow rating, refers to the maximum weight that it can safely pull along the road. For a vehicle to be able to tow a trailer or another vehicle, you need specific equipment to be installed before you can do so.
Your tow vehicle needs to be equipped with the right tow bar, tow hitch, or recovery hook to be able to pull a load, depending on the specific towing application. The maximum towing capacity for your towing hardware needs to be considered as well.
There are a wide variety of trailers that you can use for towing purposes, and these will also have their own tow ratings as well. You can have an open trailer or flatbed trailer, an enclosed trailer, or other types of trailers that can be used for hailing objects, livestock, materials, vehicles, and other items.
The tow rating of your trailer depends on the type of trailer that you choose and the features that it comes with, as well.
What Determines Tow Rating?
To determine the tow rating for your tow vehicle, your best source of information is the vehicle manufacturer. You can review your owner’s manual, or better yet, you can try calling up your dealer and get a few pointers on towing along with the information you need as well.
You may also find the trailer towing capacity listed on the driver side door jamb along with other vehicle information.
The tow rating of your vehicle is important for determining if your car or truck is compatible with the loaded trailer you are planning to tow. The gross weight of the trailer should not exceed the tow rating of the tow vehicle. If the weight of the trailer plus cargo is higher than the vehicle’s tow rating, then you will need to take some of the weight out or use another vehicle to do the job.
What Affects Tow Rating Numbers?
So what determines how much your vehicle can tow? A tow vehicle can only pull the weight as determined by the vehicle manufacturer, so there’s a hard limit on what your setup will be capable of towing in any case.
That said, you should have a good deal of headroom in terms of towing capacity, for a lot of different reasons. You want that extra capacity so you have room to adjust for trip conditions, plus you also need to consider the cargo that goes into the tow vehicle itself as well.
Most areas will have regulations that limit the weight of the load that a vehicle can legally tow. There are other considerations that you need to look into, as well, such as the maximum weight that a hitch can carry.
Your tow mount, tow ball, and other towing components are all subject to a portion of the trailer weight, and each of them has their limits. It is also important to keep in mind that when you attach a trailer, the brakes, transmission, and suspension components will all experience additional load as well.
The various tow ratings for the different components all contribute in some way to the overall tow rating of your tow setup. Vehicle and trailer manufacturers will usually provide a variety of different weight ratings to describe the towing capacity of the vehicle or trailer.
Always refer to the manufacturer’s towing capacity before loading your setup – they are there to prevent damage to your vehicle. More importantly, they can keep you and your passengers safe.
Different ratings all contribute to the maximum towing capacity of your vehicle. It’s important to understand how each of them contributes to the tow rating of your setup, so you can have a balanced setup when you load your vehicle and your trailer.
Braked VS Unbraked Towing Capacity:
The tow rating of a vehicle may refer to either its braked towing capacity or unbraked towing capacity. It’s crucial to check which rating applies to your trailer, especially if you will be loading it to near capacity. The braked towing capacity of a vehicle, simply put, is the maximum towing capacity of a vehicle assuming that the attached trailer has its own braking system.
These braking systems are connected to the braking system of your car or truck, usually by the use of a trailer cable, and they greatly increase the stopping power and control of a towing setup compared to a trailer with no integrated breaks.
The unbraked towing capacity of a vehicle, on the other hand, refers to the maximum trailer weight that the car or truck can safely pull, as determined by the manufacturer, assuming that the trailer does not come with its own braking system.
Gross Vehicle Weight Rating vs Tow Rating
One of the most common ratings cited by vehicle and trailer manufacturers is the Gross Vehicle Weight Rating or the GVWR. This rating refers to the maximum loaded weight of the tow vehicle. Trailers also have their own GVWR as well, as determined by the trailer manufacturer. As a gross weight rating, this measurement includes the weight of the vehicle plus the weight of passengers and cargo.
The GVWR is the maximum weight capacity of the vehicle, with just passengers and cargo, without the trailer. If it’s the GVWR for a trailer, then it’s the rating just for the maximum weight that it can safely carry, without considering the tow vehicle.
The tow rating for a vehicle is a measure of how heavy the trailer it can pull, so if your trailer has a higher gross vehicle weight rating than the maximum tow weight capacity of your vehicle, then you may not be able to pull that trailer if it is loaded to capacity.
Gross Combined Weight Rating vs Tow Rating
The gross combined weight rating is the maximum weight of a vehicle, filled to capacity with passengers and cargo, combined with the weight of a loaded trailer attached. Vehicle manufacturers also refer to this rating as the GCWR.
The GCWR, as determined by the vehicle manufacturer, determines the maximum gross weight that the vehicle’s power can tow, with an attached and loaded trailer taken into account.
The GCWR is usually a higher rating that the tow rating of your vehicle since it includes the passengers and cargo into consideration. On the other hand, the tow rating is the maximum weight of the trailer and its loaded cargo alone.
If you plan to load a good deal of cargo on your vehicle as well as on your trailer, it’s a good idea to check the gross combined weight rating of your vehicle along with its tow rating as well.
The GCWR of a vehicle is determined by the available torque output from the engine, as well as the ratios of the transmission. Vehicle manufacturers also take into account the capacity of the radiator, chassis, axles, brakes, and tires as well.
Since the GCWR is mainly a function of the powertrain’s capabilities, you will see higher ratings for vehicles that have the necessary upgrades in their tow package. Of course, you will have a higher tow rating for those same vehicles as well.
Gross Trailer Weight and Gross Trailer Weight Rating vs Tow Rating
The gross trailer weight is usually shortened to GTW by trailer manufacturers, and it’s the actual measurement of the total weight of the trailer fully loaded. This metric includes the weight of the trailer itself too, along with all of the items loaded onto it.
The way that the GTW is measured is by loading the trailer with all cargo and weighing it on a vehicle scale. You can also calculate the GTW by adding the gross weight of the empty trailer and adding the total weight of cargo, passengers, and fuel.
GTWR stands for gross trailer weight rating, and it’s the maximum gross trailer weight that a vehicle can safely tow as determined by a manufacturer. The GTWR is closely related to the tow rating of a vehicle, although the former usually does not take the braking system into account. On the other hand, a manufacturer may specify the maximum towing capacity for a vehicle in terms of braked tow rating or unbraked tow rating.
Tongue Weight and Tongue Weight Rating vs Tow Rating
The Tongue Weight, or TW for short, is the downward force that the tongue or coupler of the trailer exerts on the vehicle’s tow ball. It’s also sometimes referred to as the ball weight for this reason. To measure the actual tongue weight, you will need to read it off a tongue weight scale that’s been placed under the tongue of the loaded trailer.
Another simple way to calculate an estimate of the tongue weight is to take a fraction of the gross trailer weight, loaded with cargo and passengers, and use that as a guide. Most trailer manufacturers recommend that the tongue weight be somewhere within 9 to 15 percent of the gross trailer weight or GTW.
The tongue weight rating, on the other hand, is the maximum tongue weight that your vehicle and its hitch components can support. The chassis, suspension, tires, and axle of the vehicle all figures into the tongue weight rating, as well as the actual tongue weight rating of your tow bar, receiver and tow ball mount.
The tongue weight rating is a fraction of the trailer weight and the tow rating by connection. It’s an extremely important rating to consider for the safety and drivability of your setup. If the tongue weight is too heavy, it can cause the whole setup to dip under horizontal alignment which can cause dangerous steering issues.
On the other hand, too light of a tongue weight will cause the trailer to become imbalanced, which can lead to trailer sway. This is a dangerous situation to occur at high speeds, so it’s critical to have a balanced tongue to trailer weight at all times.
Gross Axle Weight Rating and Gross Axle Weight vs Tow Rating
The gross axle weight rating is the maximum weight that the front or rear axles of your vehicle can safely support. Vehicle manufacturers often refer to this rating as the GAWR – more often than not, you will also see a separate GAWR for the front axle (FR) and the rear axle (RR). The same goes for the actual gross axle weight, which is the actual weight bearing down on the front or rear axle of your vehicle.
Trailer manufacturers also specify gross axle weight ratings for their trailers. Just like the case with your tow vehicle, you should never load the trailer beyond the GAWR as determined by the trailer manufacturer.
The GAWR is an important rating for trucks, especially if you plan to use a 5th wheel hitch or gooseneck ball hitch that goes over the rear axle. A higher RR axle rating also means that your vehicle can support a higher tongue weight as well.
Curb Weight and Dry Weight
The curb weight of your vehicle is its actual weight without the additional weight of passengers, cargo and luggage. The curb weight does include the consumables necessary to operate the vehicle, including fuel, coolant, air conditioning refrigerant, motor and transmission oil, brake fluid and similar fluids. The dry weight, on the other hand, excludes the weight of all these necessities.
Tow Rating of a Tow Setup
Once you find the tow rating of your vehicle and trailer than it becomes much simpler to figure out the tow rating for your towing system. As a general rule, you should never load your trailer and vehicle beyond the lowest tow rating of your setup. If your vehicle and trailer are rated for 5,000 pounds but your hitch is only rated for 3,000 pounds, then you need to go for the lowest number as your limit.