attn: Weight Police

Maybe I am misunderstanding. All that appears to be is the guidelines for testing. My Tundra has anti-lock brakes and has a supplemental brake system. I don't understand all the jargon about brake fade and all that stuff. I still say that you load my Tundra up to 10,000 lbs and run it and a 40,000 lbs Prevost through the tests, the Tundra stops in substantially shorter distances every time. How is the Tundra unsafe and the Prevost safer?

Remember the FMVSS brakes tests are a minimum test.
Brakes are a function of the truck makers GAWRs. The truck maker designs and tests their own brake packages before releasing the truck for the minimum FMVSS tests.

"Vehicle manufacturers may determine the GVWR of a vehicle by calculating the maximum load rating of the vehicles axles, tires, brakes, frame, suspension and wheels in order to come up with a GVWR rating. Also, a manufacturer may limit the GVWR if so desired. So they could have the componentry to rate higher but choose a lower rating at their discretion."

This is true with all vehicles on the road and is a big reason dot isn't concerned with the truck makers GVWR but will nail the truck operator for exceeding the lessor of the axle/tire load ratings. Nor is my and other states that don't use a registered weight, concerned with a private vehicles registered weight. Its as meaningless number as the truck makers GVW(R) for how much load a truck can legally carry.

In other words the OP F250 Ford may have a 6100 RAWR and a 6000 FAWR = 12100 lbs of braking performance. And of as indicated in above posts the 3/4 and on ton SRW have the same mechanical brake specs.