Seeing this photo posted to another thread here
and having known loggers, the one thing I'm pretty sure of is if there were no scales between the brow and the mill, this little TT will get overloaded, often. I see it's running on a plank road so the rig will roll easier; but regardless of what aftermarket brakes the truck has to help the transmission brake, they're still relying on the ground contact of two tires to stop. I was wondering:
1) were automatic trailer brakes available in this era, and
2) what other innovative methods did these truck drivers and their mechanics use to keep everything right side up and under control on severe downgrades?
Good questions. I can't give you direct answers to them, but looking at this photo carefully suggests this truck had no auxiliary brakes since there's only a single brake rod (emergency brake) visible on the vehicles left side. Also, I don't see anything to suggest that trailer had any brakes at all.
I imagine the guys who drove rigs like this one probably never let the thing get going very fast and used the engine to manage speed. That means TT slow, and we all know what that is.
I think a truck pulling a heavy load and stopping with a load would have an aux transmission to assist the engine.
The Cordes boys can run 60 mph or so with their TT truck and trailer. Maybe they or their dad will chime in here.
In the late 20s my grandpa was hauling logs in central Florida with a TT. I'm sure that braking wasn't much of a problem in the flat country here but they used auxillary transmissions and Ruckstell axles for pulling power. I don't know if they had outside brakes or trailer brakes.
I think in severe conditions they may drag a log or something behind. The logging trains would drag a large spent cable that was wrapped around a stump or two then tie on to the other end and drag it back up when empty. My 96 year old uncle explained this to me as he was an old time logger. They were very innovative in those days.