This was a very early version of ABS. The truck was a late 80’s early 90’s model. Yes, I know the difference between electric trailer brakes and surge brakes and how they work. I also know what happened in this case.
I’m sure when he parked the truck he put it in gear and set the parking brake otherwise it would have rolled off while they were loading cattle. As is, it rolled off with him in it. He got in it and like any normal person put his foot on the brake, pulled it out of gear, started the engine and that’s when it started rolling. Dodge investigated the wreck, and we know what happened.
As far as starting one in gear, if you’ve ever fooled around with cattle, jumped in the truck with mud and cow shit on your boots you’ll learn not to do that the first time your foot slips off the clutch pedal and you break a motor mount.
Put simply, if not for the ABS actuating the truck should have sat there with the wheels locked exactly like it did for ever how long it took to round up the cattle and load them in the truck.
Some of these ABS systems in trucks are simpler than others, the simpler the better. Chevrolet’s system is the worst I’ve seen and their trucks have the worst brakes I’ve seen in a truck. Dad’s got a Suburban that takes a country mile to stop with a boat behind it thanks to the ABS. Ford’s system through 96 was fairly simple and much better that Chevy’s. The only experience I have with Dodge is the one I have now, and it’s not that bad but it’s a 3/4 ton, I don’t know if their half tons are any different. I know that the Germans worked on the Dodge suspension and I assume it’s brakes.