Transporting 2 tons in a 1 ton pickup truck

*Remove* the tailgate during the loading. It only takes a minute to do, provides at least 18" further reach into the bed for a forklift that doesn't have extension, and insures the forklift won't crunch the tailgate. The forklift can generally press up against the bumper without doing any damage.

"Pete C." wrote in news:HblCj.2951$6H.427 @newssvr22.news.prodigy.net:

My "1-ton" Dodge 3500 dually has a manufacturer's GVWR of 12,000 pounds, a rear axle rated at 10,000 pounds, a total tire load capacity on the rear axle of 12,999 pounds, and a "build weight" of 7,340 pounds.

Hauling 4,000 pounds would NOT overload this truck.

As others have said, the "1/2, 3/4, and 1 ton" nomenclature is both misleading and out-of-date.

Today's trucks are, generally, capable of hauling double the weight of similar models produced when the nomenclature was first introduced.

The problem is not between the rubber and the road, it is in the brakes themselves.

A brake converts the energy of the rolling vehicle into heat, and the heaver the load, and the faster the vehicle is rolling, the more heat gets produced. When the brake exceeds the ability to dissipate the heat that is built up, the brakes cease to function.

This is why they have those runaway truck ramps on steep hills.

That is not the issue with a pickup. The rear brakes on a pickup have far more capacity both in braking action and in heat dissipation, than the tires they work on have traction to the road surface without cargo in the bed. Add significant weight in the bed and that braking capacity becomes available.

TRUE, BUT. On an unloaded or lightly loaded Pickup, tye front brakes are doing all the work, and the rear brakes do nothing - NADA. Put close to the rated load on the truck and the rear brakes start doing their job. There is a point where you can stop the loaded truck more quickly than the empty truck. Varies from truck to truck, and with load position, but a well loaded pickup can definitely stop as well, if not better, than an empty truck. Overloaded is a different story - and what, exactly defines overloading, brake-wize, varies from truck to truck. A Super Duty with 4 wheel disk brakes generally has more brake than tire with single rear wheels.

Not normally, no - but a properly motivated idiot driver can get the brakes hot enough to heat-fade to nothingness on almost any vehicle.

Passenger cars have enough reserves that getting the brakes that hot takes a concerted effort. But pickups and small rental trucks are often overloaded far above safe levels and taken down mountain passes at "normal highway speeds" that are WAY too fast for conditions considering the overload.

And they don't normally pull over small pickup trucks and box vans on a whim and send them to the scales if they suspect an overload, or run them all through the regular highway scale stations and issue them tickets for overloading. It usually only becomes an issue at the coroner's inquest after the "K-injury" (fatal) accident...

And that's why good trucks (Toyota for one) put a simple and cheap all-mechanical Load Sensing Proportioning Valve on the rear axle brake line, with a ride-height sensing arm going up to the chassis.

Empty truck, springs full up, LSPV arm sets it to minimum pressure, and the brakes cut off before rear wheel skidding really gets started. With weight transfer to the front axle, you can practically lift the rear wheels off the ground in a panic stop, and this would lead to serious control and stability problems.

Full truck, springs full down, LSPV set to wide open, and the rear brakes will do all they can to help. And if the CG is very high or far forward of the axle centerline, and the weight shifts forward in a full panic stop, the LSPV will still kick in to keep the rear from skidding.

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An additional issue with an unloaded 1 ton truck is the ABS system. When the rear axle goes over a bump during braking with the stiff suspension and no cargo the wheels will bump up clear of the road and momentarily stop turning which the ABS incorrectly interprets as the rear wheels locking and promptly freaks out leading to a loss of braking and a longer stopping distance. You quickly learn to scan the road while braking and momentarily let off the brakes when you hit a bump.

Actually, over the last few years this is not true. Most passenger cars today have borderline braking capacity at best. They are made as light as possible, and with ABS you never need/want enough braking to lock the wheels on dry pavement anyway. I could fade the brakes out on any of my last 3 cars in virtually NO time, without more than half trying. Overloaded on a mountain pass you can take out ANY amount of brake if you don't know how to drive.In normal operation, trucks tend to be closer to overbraked than most cars. (some sports cars and light duty pickups excepted, of course).