Do You Have Enough Trailer Towing Capacity?

You need to know trailer towing capacity before you can safely tow a trailer. Don't expect your boat towing insurance to pay for the damage if you try to pull too much weight with an undersized vehicle. Towing looks simple enough, but it puts a big strain on your vehicle and affects handling. Here's what you should know before you tow.

Check the Measurements
Tongue weight is a major component of the towing capacity equation. Too much tongue weight may cause suspension or drivetrain damage to your vehicle. Excess weight pushes your vehicle down in the back, causing the front wheels to lift. If you've got a front-wheel drive vehicle, that could leave you stuck at the side of the road. Even in a rear-wheel-drive vehicle, you'll notice changes in traction, braking and steering response.

Too little tongue weight may lift the back of the vehicle while you're towing. This reduces braking and rear wheel traction, causing an unstable situation that could result in jackknifing or tail wagging.

Your owner's manual should contain some information about towing, but it may be presented in terms that you don't quite understand. Here's what the most common terms mean:

• Base curb weight is the weight of the tow vehicle, including a full tank of gas and standard equipment.
• Cargo weight, or payload, is any weight added to the base curb weight. This includes cargo, optional equipment and the trailer tongue weight.
• Gross axle weight (GAW) is the total weight on each axle. Figure the front axle weight by placing the front wheels on a scale with the trailer hitched to the vehicle. Pull forward so that all four wheels, but not the trailer, are on the scale. This number is the GAW. To learn the axle weight for the rear axle only, subtract the front axle weight from the GAW.
• Gross axle weight rating is the total weight each axle can carry. These weights can be found on a sticker on the driver's side front door. They should also appear in your owner's manual. Never allow the individual axle weights to exceed the GAWR.
• Gross combination weight (GCW) is the weight of the loaded tow vehicle plus the weight of the loaded trailer. The gross combination weight is obtained by weighing the tow vehicle and the trailer together on a scale.
• The gross combination weight rating (GCWR) is the maximum allowable weight that the powertrain can handle without damaging the vehicle. This includes the gross combination weight, the weight of all the stuff in your vehicle, the weight of the trailer and what it's carrying and the weight of the driver and any passengers.
• Gross vehicle weight (GVW) is the base curb weight plus the weight of the driver, any cargo and any passengers in the tow vehicle.
• Gross vehicle weight rating (GVWR) is the maximum allowable weight of a fully loaded vehicle, including the driver and passengers. Never allow the GVW to exceed the GVWR; you'll risk damage to your powertrain and suspension.
• Maximum loaded trailer weight is the weight of the trailer when it is fully loaded.

Doing the Math
The maximum tongue load should not be more than 200 pounds for trailers with a gross loaded weight of up to 2,000 pounds gross loaded weight. For trailers over 2,000 pounds, the tongue weight should be 10% to 15% of the trailer weight.

You can measure the tongue load by disconnecting the trailer from the tow vehicle and placing the tongue onto a scale, with the coupler at the same height as the hitch ball on your vehicle. If the tongue load is higher than the weight limit, move things in the trailer toward the back weigh it again. If the tongue load is beneath the minimum limit, move items toward the front of the trailer.