Transmissions and Axles
Mack Sheesley, Phoenix, Arizona
A standard in drivetrains
1930, the system we recognize as standard today, using a disk clutch, a lever
shifted gear transmission, a tube-type drive-shaft with universal joints, and an
enclosed rear axle had won the truck designers' favor. Practicality had done
away with the husky chain drives, the sliding-cone friction clutches,
primitively shifted planetary transmissions, experimental belt-drive
differentials, and other fanciful chassis gadgetry.
Since then, the blueprints on draftsmen's tables and the machined
models in experimenters’ workshops focused on producing clever engineering
improvements of these basic components that resulted in the sophisticated truck
of today. Despite all the modernization, however, the same basic machinery still
spins under there. But instead of a well-trained driver, an electromechanical
genie monitors, regulates, and shifts.
For the whole story, subscribe to Old Time Trucks® and read the
Dec04/Jan05 2004 issue.