They do, BUT… there are two types of automated transmissions for them. The first is a true automatic, such as the Allison, and is typically used on vocational trucks, off-road vehicles, military vehicles, etc. In the 70s and 80s, they were mechanical, but now they’re electronically controlled. The other type is the…

You're telling me the dog depressed the brake valve and put it into drive simultaneously? I think he more likely bumped into the shift column of s manual truck after the driver forgot to set his brakes.

Well, the thing of it is… you got it wrong, too. One knob is the brake control valve for the tractor, which releases the tractor spring brakes. The other is the trailer supply valve, which supplies a constant supply of air to the trailer, again for releasing the spring brakes. Maybe it would help to know what you're…

That's what I was thinking. I don't see the dog just pushing in the MV3 valve then putting it into gear. I could see a dog getting excited, running into the shifter, and setting into motion a truck where the brakes were already released, though.

My guess would be that the driver forgot to pull the brake control valve in the first place. The MV3 valve takes a good amount of pressure to actuate, and while I wouldn’t rule it out as impossible, I’m skeptical the dog applied slow, steady pressure to it then put the truck into gear.