Automatic Car Expert: The L.A. Driver Dictionary, A to D

Don’t know a dual-clutch transmission from a cylinder deactivation? No big deal. This glossary of car terms is all you need. (Part one of three posts)

Adaptive Cruise Control


This feature revamps 1940s technology by using laser or sonar to automatically brake or accelerate your car, maintaining a constant distance from traffic ahead. Terrifying at first (but indispensible once you’ve fully relinquished control), adaptive cruise control is capable of making the inevitable L.A. slog tolerable.

Ex.: “At first I was scared to let my car make its own decisions, but now I can’t live without my adaptive cruise control.”

All Wheel-Drive


A car’s engine can drive front wheels, rear wheels, or—in this case—all four. Contrary to popular belief, all wheel-drive might not keep you from spinning off a wet onramp because you’re late for your reservation at Gjelina. But it may help you claw your way out of Hungry Valley, if paved roads aren’t your thing.

Ex.: “My car’s all wheel-drive didn’t do crap for me when I wiped out on the 405.”

Anti-Lock Brakes


Anti-Lock Brakes (or ABS) keep your car in control during hard stops by pulsing several times a second, preventing skids during once-in-a-blue-moon LA downpours. Pro tip: In an unlikely event of panic braking, don’t let off when you jam your ABS-equipped stoppers to the floor.

Ex.:Anti-lock brakes saved my bacon when I was twiving (tweeting while driving) and didn’t notice the light turned red.”



This fuel combines petroleum-based diesel with plant-based diesel, from sources like French fry oil and corn oil. A common retrofit on 1970s and 1980s-era Mercedes-Benzes, biodiesel has assumed a strong cultural (read: hipster) following.

Ex.: “That biodiesel 190D wagon smells like it’s farting In-N-Out.”

Center Stack


Not to be confused with the flapjacks served at Du-Pars, this array of buttons is what separates the left and right sides of your instrument panel. Here’s where you’ll typically find controls for navigation, air conditioning and audio, and accessories nobody uses, like hazard lights.

Ex.: “Hit the A/C, would ya? It’s right there, on the center stack.”

Clean Diesel


Diesels built a bad rep for blowing smoke like a politician, smelling like an oil refinery on four wheels, and sounding like claptrap contraptions. But thanks to innovations like ultra low sulphur fuel and particulate filters, diesels are a quieter, cleaner burning alternative to conventional gasoline. Best of all, they yield hybrid-like MPGs while delivering strong pulling power, making them unrecognizable compared to their stinky, wheezy, former selves.

Ex.: “My clean diesel BMW makes me never want to go back to gasoline again.”

Continuously Variable Transmission


Unlike conventional transmissions (which uses individual “speeds”, or gears), a continuously variable transmission (aka, CVT) has a nearly infinite array of gear ratios by using a belt-and-pulley arrangement. Though smooth running, CVTs are typically found on lower performance models; you won’t find one on a Ferrari.

Ex.: “The Subaru Forester rocks, even though it’s got a continuously variable transmission.”

Curb Weight


This unit of measurement describes the weight of a vehicle when it’s ready to drive—that is, when it’s got a full tank of gas and no passengers onboard. Lower curb weights can boost a car’s performance and fuel economy, which has led automakers to actively reduce weight for quicker acceleration and better MPGs.

Ex.: “The dealer told me the C-Class has a curb weight that’s 220 pounds lighter, which will cut my fuel costs.”

Cylinder Deactivation


An engine feature that shuts off cylinders for reduced fuel consumption during coasting (not to be confused with auto stop start, which turns the engine off when stationary).

Ex.: “The only way to tell my Cadillac’s cylinder deactivation has kicked in is to look for the light on the dash.”

Dual-Clutch Transmission


Using two clutches which operate two separate gear sets, dual clutch (or twin-clutch) transmissions are able to simultaneously disengage one gear while engaging another, enabling smooth shifts. Mad scientists at the Volkswagen Group were early proponents of this technology, plopping dual-clutch gearboxes into everything from VW Golfs to two million-dollar Bugatti Veyrons. Other automakers have since followed suit, much like chefs chasing the bacon fad.

Ex.: “I’d totally buy an Audi R8 now that it’s got a dual-clutch transmission.”