At the risk of repeating myself (which I'm clearly doing), where the hell are the wheel chocks?

A nice heavy load at 5 mph is more energy than an unloading at a dock should produce...or do you not realize how much energy is there to be stopped at 5 mph with a 40-47k lb load ...And I've never had any issues at docks with just trator set...and that's real life not interet theory of a pretend driver or wanna be future driver...Now I have seen drivers who have set their trailer breaks in cold weather while at a dock for a coupe hours end up with stuck trailer breaks...LOL dumb-A$$ .

And these should be provided by receiver ,but obviously were not .

So that makes it okay not to use anything to chock the wheels then, right?

I'm sure the TMC driver had blocks of wood somewhere on his truck that he could have used. And yet, he didn't.

A wheel chaulk is a wheel chaulk a piece of wood is a piece of wood ...

First of all, the fools that only set the tractor brakes at the loading docks are the very reason that many places will not load or unload if the wheels are not chocked. I've been on a surface that was slick enough, that with the brakes set on tractor and trailer, and a chock in front of two trailer tires, when the forklift went into the trailer and stopped, the rig slid forward enough to drop the dockplate. And, two docks over, the truck also slid ahead, but enough to bunp the trailer of a truck parked in front of him.

In the pics, as the load was being driven off the truck, the weight shifted from the drives to the trailer. I'ts entirely possible that the driver DID engage the tractor brakes. But, without the trailer brakes engaged as well, the inertia of the load moving back could have moved the rig forward. May not sound possible, but I've hauled farm machinery before. Some of them can do some very strange things. Wish I had pics of some of them.

Also, who ever was on that AG tractor should have realized that the wheels were turning, but wasn't getting any closer to the dock.

I guess you've never unloaded at a place that uses 4X4 blocks of wood as chocks.

Every Menards hardware store in existence comes to mind. And they use them for flatbeds too (like they should).

The brake cylinder pushes on the pushrod, which pushes the slack adjuster, which (most of the time) rotates an s-cam, which presses the brake linings against the drums, creating friction and stopping the truck.

Whether you apply air pressure to the brake chamber to provide the force, or vent the air pressure holding back powerful springs to do it(parking brake)....you're doing the same thing.

Yes Tom...You can "pop" the brakes at 5mph to stop the truck. Your still going to cause component failure, because the "Spring Brake" is not designed to stop a moving truck. It is designed to hold in place a stopped truck.

Once you pull the buttons, you have no recourse. You don't have time to release the brakes to prevent damage. Damage to components can include damaged "S" cams, pads pulled off of rivets, blown brake chambers and even drums can be cracked, from the inertia of the moving vehicle.

Big Jeep had it right when he made this statement;

:hellno::hellno::hellno::hellno:

I don't agree, but this isn't the time, place, or thread for an argument...:)

Regardless, he certainly should have set his brakes and chocked his wheels...driver error, IMHO...:angryblue: