As far as most folks are concerned, transmissions operate on the principles of witchcraft and sorcery, consisting of a bunch of gears sloshing around in a bunch of fluid, and moving the car forward when it’s put in Drive.
Inside of a transmission, shafts, gears, cogs, passageways, pumps, bands, clutches and fluid lines are all packed into an incredibly small space, all working to turn the mechanical force generated by your ride’s engine into the miracle of forward momentum.
Transmissions were once simple, low-tech, and about as sophisticated as a pasta salad. Today, with the latest advances and cramming of nine gears or more into a single gearbox, transmissions are incredibly difficult to explain without multiple diagrams, animations and physics lessons. But explain we shall – and below, we’ll take a look at few vital bits of the transmission, some specialty transmissions, and some of your writer’s favourite examples of each.
By time you finish reading our guide, you’ll have a more comprehensive understanding, which will make you more educated, more awesome, and more appealing to the ladies/blokes.
The Gist: Manual or automatic, 5 gears or 10, dual-clutch or manual, a vehicle’s transmission has a simple job. It allows the engine to operate at a fairly narrow range of speeds (RPM) while enabling the vehicle to operate at a much wider range of speeds. The gears used in the transmission help make the best possible use of the engine’s torque, with shorter gears used to take off and accelerate, and taller gears are used to keep the engine revving slowly to save fuel while cruising at speed.
Keep This in Mind: Whatever the sort of transmission we delve into below, remember this simplified fact: a transmission receives power from a shaft connected to the engine, and transmits power to the wheels via another shaft which connects to them.
Manual Shifting: Do you drive a manual? If so, you’re a champ, a boss, and we’d like to buy you a coffee.
Also, your transmission is the easiest to simplify and explain. In simplified terms, one shaft enters the transmission from the engine and is constantly spinning at the same RPM as the engine. Another shaft is connected to the wheels, and always spins at the speed of the vehicle’s wheels.
Gears connect the two shafts to each other, and when one gear on one shaft meshes with one gear on the other shaft, one shaft drives the other, sending the engine’s power to the wheels.
The gears are constantly meshed, but synchronization rings lock different gears into place on the shaft depending on the gear selected. This engages a different gear ratio and either speeds up, or slows down the output shaft. ([With thanks to Blur911 on our forum])
In neutral, the gears aren’t locked in by the syncro rings, – meaning the input shaft and output shaft can spin freely of one another.
Moving the shift lever controls which sets of gears are engaged with each other, effectively altering the gear ratio in use.
Notable Manuals: Your writer is fond of numerous manual transmissions, key among them belonging to the Mazda MX-5 for its precise, fast-shifting and finely-honed feel, the Porsche Cayman for its springy and smooth action and wrist-flick throw, and the Dodge Challenger SRT8, because of its manly, beefy and heavy-duty feel that’s pure testosterone.