First, let’s start with defining the technical terms.
Gross Vehicle Weight Rating (GVWR) - The maximum operating weight/mass of a vehicle as specified by the chassis manufacturer. Essentially, how much the vehicle can carry with everything including chassis, body, fluids, fuel, passengers and cargo. Trailers are not included in this rating.
Chassis manufacturers always will publish this weight. It can be found on the sticker placed within the front drive side door frame or on the chassis manufacturer’s website.
Curb Weight - The total weight of a vehicle with all operating consumables including oil, coolant, refrigerant and fuel. Include the weight of a truck body if applicable in the curb weight. This number will not include the weight of passengers and cargo within the vehicle.
This number will come from the chassis manufacturer as well and can be found on their website. If your work truck has a body, be sure to include the body weight (including the bumper, mounting kit and shelves if applicable) within the curb weight as well. Body weights should be located on the body manufacturer’s website.
Payload- The difference between Gross Vehicle Weight Rating and Curb Weight. Simply put, it is the amount of weight left that your vehicle can carry in passengers and cargo.
The equation to calculate your work truck’s payload is:
GROSS VEHICLE WEIGHT RATING (GVWR) - CURB WEIGHT = PAYLOAD
LET’S RUN A QUICK EXAMPLE. LET’S SAY YOUR TRUCK’S GVWR IS 10,000 LBS AND YOUR CURB WEIGHT IS 7,100 LBS. WHAT IS YOUR PAYLOAD?
Answer:10,000 lbs (GVWR) - 7,100 lbs (Curb Weight) = 2,900 lbs Payload
This may sound like a lot of payload but keep in mind a few things. Your payload doesn’t include passengers, at the very least your vehicle will have one passenger (the driver) and use up 150 lbs (or more) of payload. If you have multiple passengers, account for those as well. Don’t forget your tools, parts and materials you will carry on your truck. On upfits like a service or utility body, there is ample space to store these items. Calculate the weight of these items carefully and don’t underestimate. Also, be sure to account for any items you install on the truck or body after calculating the payload. These could include a grill guard, ladder or material rack, toolbox, generator, compressor, welder, auxiliary fuel tank and more. Lastly, keep some payload on reserve! There are times when you will need to carry additional equipment, tools or materials to the job that were not included in the original payload calculation. If you leave ample payload open, this won’t become an issue.
SOURCE: WT Payload
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