GCVW – Gross Combined Vehicle Weight (GCVW) is the total combined weight of a fully loaded vehicle, including passengers, payload and everything in tow.

GVW – Gross Vehicle Weight (GVW) is the total weight of a fully loaded vehicle, including passengers and payload – but excluding all towing.

GTW – Gross Trailer Weight (GTW) is the total weight of the trailer plus all the cargo in it.

CURB WEIGHT – The weight of a vehicle without any passengers or cargo, but including all necessary fuel, fluids and standard equipment.

TRAILER TONGUE WEIGHT – The downward force exerted on the hitch ball by the trailer coupler. In most cases, it should fall between 10 to 25 percent of GTW.  Trailer tongue weight must be accounted for in total payload.

REAR AXLE RATIO – The ratio between the revolutions per minute of the driveshaft and the rear axle. In general, a higher number offers more towing power; a lower number offers better engine efficiency.  How does axle ratio affect my towing and payload capability? (Applicable to pickups and Chassis Cabs only.)  In general, a higher axle ratio offers more towing power and quicker acceleration, while a lower axle ratio offers better engine efficiency and quieter running.  The axle ratio describes the relationship between the driveshaft revolutions per minute and the rear axle”s revolutions per minute. For example, an axle ratio of 4.1:1 means the small pinion gear at the end of the driveshaft must rotate 4.1 times for every single rotation of the rear axle.  Finding your ideal axle ratio will be a compromise. You want a ratio that will give you good towing power without handicapping your non-towing performance too severely. By determining how much weight you”ll be towing and how often you”ll be towing it, you”ll be able to find a ratio that will maximize both power and engine efficiency.