Every vehicle is assigned a maximum towing capacity by the manufacturer. This number indicates, in pounds, the maximum weight of a trailer that a specific vehicle is capable of safely transporting with a stock configuration. The towing capacity is determined by the ability of a vehicle's components to safely and efficiently handle the weight of an increased load. In order to move a trailer, the engine must produce enough horsepower, while the brakes must have sufficient power to stop the load. Modifications to the various systems of a vehicle may help increase the towing capacity.
Evaluate the weight of the trailers that you would like to tow in relation to the tow vehicle's maximum towing capacity. If the trailer exceeds the tow rating by more than 1,000 to 2,000 pounds it may be best to use a different vehicle for towing. However, if the difference in weights is within a reasonable range, begin planning modifications.
Purchase and install an aftermarket power programmer for the truck. These devices create added horsepower and torque, giving the vehicle additional power to pull heavier loads and work with the vehicle's electronic control module to modify automatic transmission shifting for better handling while towing. Programmers are typically application-specific and based on the make and model of the truck.
Work with a professional mechanic to upgrade the braking systems on the truck. It is imperative that the tow vehicle is able to safely and efficiently stop with a heavier load. Upgraded brake rotors and pads will help create more powerful braking. Simultaneously, work to equip the vehicle with an electronic trailer brake controller that will allow the driver to adjust the stopping power of the trailer's braking system while driving.
Upgrade the axles and differentials of the truck with heavier-duty parts. Although this is an expensive upgrade, an improved gear ratio will allow heavier loads to be towed without causing undue stress to the truck's drive train.
Install a hitch capable of handling the increased weight load that you plan to tow. Many vehicles come standard with a Class III hitch, rated for loads of up to 5,000 pounds. However, the addition of a higher class hitch will allow the safe transport of heavier loads. For example, upgrading to a Class IV hitch can increase the hitch capacity to 10,000 pounds.
