your able to push your 6000 lb truck when your out of gas,i could tow over 85,000 lbs with a truck 1/4 the size of the load.Ok wat ime getting ay is the tow ratings aught to be changed to a different standard,i mean there is only 4 contact patches the size of you hand,thats why ime able to push a 3 ton vehicle around,and 18 contact patches are all that meets the road.How bout a DRAG test. put a 2000 lb load on a skid,test on 2 reaonable surfaces,asphalt and dirt.use a control of some type,say a wood skid to provide friction,or a concrete block on concrete.i think that all the big boys will have a real test of grunti. I think a sizable slab of crete on crete would do the trick , a "dead lift" for trucksor rig a system of pullys to actually lift a block,while still pulling in a strait line.I wonder if it would work,,what do you think?..maybe?  

Actually a simpler tow test for effective towing power is a weighed trailer on a grade. By measuring the grade and GCVW you can calculate how much HP is actually being produced or delivered. Getting a wheeled load moving on flat ground is not really a test. A old 30HP tractor properly weighed can easily out pull 6000 lb 300 HP 4x4 in a dead pull in dirt and mud but the hill test at speed shows how much towing HP you really have. Below are a few links related to this test.

This first link shows needed flywheel HP for various grades and loads...
Click Here

This second link shows the drive shaft torque needed with various axle ratios...
Click Here

And this last link shows the effect the tire size has a relative pulling power with a constant input torque to rear axle.
Click Here  

thanks snowman! when they do the vehicle testing here they hook a weighted trailer with a large flat "screen" looking thing set up on a trailer crosswise to the airflow coming off the truck,figured they were testing power,fuel consumption,durability type stuff.theyed run to San Antonio and stuff