Grandpa's beer hauling 1935 Chevy tractor-trailer rigs got retrofitted with a vacuum booster for the original mechanical brake system, a cylinder that basically made the driver's right leg stronger- - - -still had no trailer brakes, however! They hauled bottles and kegs from Milwaukee and St. Louis to Nashville in the mid-1930's. Sadly, no pictures of those rigs survived!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!