CalculateY
Quick Answer
A vehicle with a 15,000 lb GCWR, 5,000 lb curb weight, and 500 lbs of passengers and cargo has an estimated maximum towing capacity of 9,500 lbs.
Vehicle specifications
Gross Combined Weight Rating from vehicle manual
Vehicle weight without passengers or cargo
Items loaded in the vehicle (not on trailer)
Trailer details
Total loaded weight of the trailer
Downward force on the hitch (10-15% of trailer weight)
Common Examples
| Input | Result |
|---|---|
| GCWR 15,000, curb 5,000, passengers 400, cargo 100, trailer 5,000 | Estimated 9,500 lbs max, 4,500 lbs remaining capacity |
| GCWR 10,000, curb 4,500, passengers 350, cargo 50, trailer 4,000 | Estimated 5,100 lbs max, 1,100 lbs remaining |
| GCWR 20,000, curb 6,500, passengers 500, cargo 200, trailer 10,000 | Estimated 12,800 lbs max, 2,800 lbs remaining |
| GCWR 26,000, curb 7,500, passengers 500, cargo 300, trailer 12,000 | Estimated 17,700 lbs max, 5,700 lbs remaining |
| GCWR 7,500, curb 4,000, passengers 300, cargo 100, trailer 4,000 | Estimated 3,100 lbs max, over capacity by 900 lbs |
How It Works
The formulas
Total Vehicle Weight = Curb Weight + Passenger Weight + Cargo Weight
Maximum Trailer Weight = GCWR - Total Vehicle Weight
Remaining Capacity = Maximum Trailer Weight - Actual Trailer Weight
Tongue Weight Percentage = (Tongue Weight / Trailer Weight) x 100
Where:
- GCWR (Gross Combined Weight Rating) is the maximum allowable weight of the fully loaded vehicle plus the fully loaded trailer. This value is set by the vehicle manufacturer and found in the owner’s manual or on the driver’s door jamb sticker.
- Curb Weight is the weight of the vehicle with all standard equipment and a full tank of fuel, but no passengers or cargo.
- Tongue Weight is the downward force the trailer exerts on the hitch ball. For conventional trailers, this should be 10% to 15% of the total trailer weight. Too little tongue weight causes trailer sway. Too much tongue weight overloads the rear axle.
GCWR vs. GVWR
GCWR and GVWR are different ratings. GVWR (Gross Vehicle Weight Rating) is the maximum allowable weight of the vehicle itself, including passengers, cargo, and tongue weight. GCWR is the maximum combined weight of vehicle plus trailer. The towing capacity calculation uses GCWR because it accounts for the entire system.
Tongue weight and stability
Tongue weight affects how the trailer tracks behind the vehicle. The industry standard recommendation is 10% to 15% of total trailer weight for bumper-pull trailers. Fifth-wheel and gooseneck trailers typically have 15% to 25% tongue weight, which improves stability at higher speeds. A tongue weight below 10% increases the risk of trailer sway, particularly in crosswinds or when passed by large vehicles.
Worked example
For a vehicle with GCWR of 15,000 lbs, curb weight of 5,000 lbs, 400 lbs of passengers, and 100 lbs of cargo towing a 5,000 lb trailer with 600 lbs of tongue weight: Total vehicle weight = 5,000 + 400 + 100 = 5,500 lbs. Maximum trailer weight = 15,000 - 5,500 = 9,500 lbs. Remaining capacity = 9,500 - 5,000 = 4,500 lbs. Tongue weight percentage = (600 / 5,000) x 100 = 12.0%, which falls within the recommended 10-15% range.