Towing guides

Longer explanations of the maths behind the calculators - how to do it by hand, how to measure it for real, and what goes wrong when the numbers are off.

• How to Calculate Tongue Weight (and Why 10-15% Matters) The formula, three ways to measure it for real, and what happens at the edges of the range.
• Towing Capacity vs Payload vs GVWR: What Actually Limits You Four ratings, and why the one that stops you is almost never the tow rating on the brochure.
• How to Set a Trailer Brake Controller (Gain, Explained) What gain actually does, how to set it in a parking lot in ten minutes, and how to tell when it is wrong.
• How Much Does Towing Affect Gas Mileage? What the fuel penalty really is, what drives it, and how to estimate the cost of a trip.
• How to Weigh a Trailer at a CAT Scale The two-weighing method that gives you every number these calculators ask for.