Aug 9, 11 | by: By G. R. Whale
Pulling You Weight
How much can you really, legally, tow?
Some years ago at an RV show, while inspecting a 40-foot Teton fifth-wheel, the potential buyer was told he could pull it with a 3/4-ton pickup. I laughed. When the customer asked about my reaction, I explained there was no 3/4-ton that could carry the trailer’s 4,000-plus-pound pin weight nor tow its 20,000-plus-pound loaded weight.
The frowning salesman questioned my credentials (I was technical editor at an RV magazine) and got quite irked when I advised the customer he’d also need a license endorsement to drive it in his home state.
Much to the salesman’s disgust, the customer walked out armed with the truth about towing capacities.
Tow ratings are big business in pickups, bragging rights perhaps second only to horsepower and torque. Vehicle manufacturers present the maximum-weight scenario when it comes to towing capacities of pickups. The opposite is quite often the case with trailer builders that often offer the lightest weight regarding empty trailer weights.
In both instances, reality and gravity tend to get the last word.
Such numbers are critical if you are a contractor and tow anything with your pickups. Tow more than what your particular truck is really rated for and your company is wide-open to insurance and liability issues.
Do the Math
Curiously, two of the primary numbers you need to determine your truck’s maximum towing capacity rarely appear on the government-mandated door jamb certification label and tire rating label: Gross Cargo Weight Rating (GCWR) and your truck’s weight as equipped.
Note: Only the vehicle manufacturer has the authority to set or adjust GCWR.
Let’s build a generic 1-ton regular cab 4WD diesel dually pickup with fictional but typical numbers (all in pounds): Base weight 7,500; GVWR 12,500; payload 5,000; GCWR 29,000; max conventional tow 14,000 (8,000 without weight-distribution hitch); max fifth-wheel tow 21,346; GAWR front 5,500; rear GAWR 9,350; and empty axle weight 4,300 front, 3,200 rear.
The first thing you should notice is the axle ratings add up to more than the truck’s max loaded weight of 12,500 pounds, and the payload rating is less than what the rear axle can accommodate given its empty weight. But that doesn’t increase GVWR, GCWR or payload.
Next you’ll see the tow rating is GCWR less base weight and a 150-pound EPA “standard” driver.
If your foreman’s called “Moose” for a reason, the fifth-wheel hitch hardware added 75 pounds, you carry 50 gallons of diesel in a refuel tank, a small cooler and a tool box, take another 700 pounds off the max rating.