GCWR vs. GVWR
“Know before you tow,” is an easy way to remind drivers and fleet managers to check their vehicles Gross Combination Weight Rating (GCWR) before putting drivers and vehicles on the road.
At times it can be difficult to determine the GCWR and you may need to take into account the GVWR as well.
What is the Gross Vehicle Weight Rating (GVWR)?
The Gross Vehicle Weight Rating (GVWR) is determined by the manufacturer and takes into account the base curb weight of the vehicle plus the weight of any optional accessories, cargo and passengers.
You should never load a vehicle beyond the listed gross vehicle weight rating.
What is the Gross Combination Weight Rating (GCWR)?
The Gross Combination Weight Rating (GCWR) is the maximum safe weight of both:
- the loaded tow vehicle, and
- the loaded trailer
But what is so important about the GCWR? Here we answer your questions.
Where can I find the maximum GCWR for my vehicle?
Manufacturers determine the maximum weight rating for each vehicle, and it can be found on your vehicle placard. However, if this information is not available, it is possible to calculate your own.
How can I calculate my vehicle’s Gross Combination Weight?
You can use the use the following formulas to calculate your vehicle’s GCWR:
GROSS VEHICLE WEIGHT (GVW):
Vehicle Base Curb Weight
(vehicle + full fuel tank + standard equipment, but NOT passengers)
(cargo + extra equipment + trailer tongue)
LOADED TRAILER WEIGHT (LTW):
Weight of empty trailer
Weight of anything on or inside trailer
GROSS COMBINATION WEIGHT (GCW)
GVW + LTW (above numbers) = GCW
How do I find the actual weights of these separate items?
A local public scale is needed to weigh either the separate items or weigh a fully loaded vehicle and trailer.
What are the problems with exceeding the GCWR?
- You may damage your vehicle or your trailer by exceeding the weight limits.
- You put your safety and the safety of others at risk.
- You risk being unable to control your loaded vehicle. Slowing and stopping becomes difficult or impossible.
What kind of brakes do I need to manage my vehicle and trailer load?
It’s important to note that vehicle brakes are only rated for the Gross Vehicle Weight, NOT the combined weight.
If the Gross Combined Weight surpasses the Gross Vehicle Weight, you should use separate trailer brakes.
Why is it important to know the GCW?
Single-unit vehicles, by themselves, may not qualify as a Commercial Motor Vehicle (CMV). However, the addition of a trailer—or any weight—may put the vehicle over the threshold, causing it to be considered a CMV.
With the additional weight, this vehicle combination may now require the driver to have a Commercial Driver’s License (CDL), therefore, it is important to know the Gross Combined Weight to ensure that the driver has the proper license.
Knowing your vehicle’s Gross Combined Weight Rating is more than just a policy, it’s also a way to ensure safety is upheld for all drivers on the road.