How Automatic Transmission Works

If you own a car with automatic gearbox, you’re probably curious to know how automatic transmission works. Turns out the modern automatic transmission is the most complicated mechanical component in an automobile. It contains mechanical systems, hydraulic systems, electrical systems and computer control, all combining their forces to make a car run smoothly. This article means to explain how automatic transmission works and what you can do to keep it in good condition or notice in reasonable time if something is wrong with it.


The main differences between a car with automatic transmission and one with manual transmission are that the first has no clutch pedal and no gear shift. Once you put the transmission into drive, everything goes automatic. Though both transmissions achieve the same thing, they do it through different methods; they allow the engine to operate smoothly in its narrow range of speeds, while providing a wide range of output speeds. If it weren’t for transmissions, cars would be limited to one gear ratio which would have to be selected to permit the car to drive at a desired top speed. Therefore, the transmission uses gears to make better use of the engine’s torque and to keep it running at an optimal speed. Another difference between how automatic transmission works and how manual transmission works is that the latter locks and unlocks different sets of gears to the output shaft to attain various gear ratios, whereas with the first the same set of gears can produce all the different gear ratios needed.

In order to better understand how automatic transmission works, we must take a look at the ingenious parts that form it. First, we have the planetary gearset, which is the one responsible for creating all the different gear ratios that the transmission can produce. Other parts, like the set of bands that lock parts of a gearset, the set of three wet-plate clutches, the hydraulic system and the gear pump that moves transmission fluid around, only serve to help the planetary gearset work as it’s supposed to. The planetary gearset has three main components: a sun gear, the planet gears and their carrier and a ring gear. All these components can be input, output or held stationary.

The technology and science that make the automatic transmission work is all very complicated and complex and only someone used to car components and physics could entirely understand all the work that went in there. Still, that doesn’t mean that the common driver can’t know a bit about it, at least enough to realize when something is wrong and needs repair. First of all, one should watch for leaks and stains under the car, as that may come from the transmission and could affect the power steering system. Secondly, the transmission fluid should be checked regularly for color and odor and the driver should pay attention to new noises, vibration and shift behavior.

Manual Transmission

   In order to understand how manual transmission works, we need to know what a car needs it for. That’s torque, and it makes the car move. The inclination of the road surface, the car’s weight and other engine characteristics combined dictate what amount of torque is necessary to smoothly drive along.


Engines by themselves are not constant-torque devices, and since we can’t drive an engine at constant speed, it needs to be attached to something that mechanically multiplies the torque to allow a smooth operation. And that is what a manual transmission does; it smoothes out the torque curve of the engine to permit the car to start off and to accelerate at a desired level. Then you are able to drive at the highest speed with the engine running at its most efficient level.

A manual transmission is made up of several shafts, like the input shaft, the output shaft, the layshaft and a reverse gear. All the gears are mounted on the shaft. Though there is no limit to the number of gears that a manual transmission can have, common practice limits them to 6 forward speeds. Each of these gears perfectly fits its counterpart on the layshaft. Each gear is cut with a number of teeth that allow it to produce a desired ratio, which creates torque multiplication. The gears in a manual transmission don’t move, except the reverse. All of them are in constant alignment with their counterparts.

Another important part of the manual transmission is the synchronizer, a bronze ring that sits next to the gear and helps create a friction that slows the speed of the assembly enough for the shift hub’s spline to grab the teeth from the synchronizer and gear sprocket.

Manual transmission is what allows the gear ratio between the engine and the drive wheels to change as the car speeds up or slows down. The reason we shift gears when driving is so the engine can stay below the redline and near the rpm band of its best performance. All the parts in a transmission are assembled with extreme precision, and the whole assembly sits in a pool of gear oil, so that you can drive without glitches. This is why we must treat the gearbox with respect, that is to say, we must learn how to properly use it in order to avoid causing big damage to the car’s engine.

Bugatti Veyron

Bugatti Veyron is a mid-engined grand touring car, designed and developed by the Volkswagen Group and manufactured in France by Bugatti Automobiles. With a slick, Batmobile-like appearance, Bugatti Veyron is one of the most desired automobiles in the world, especially since its Super Sport version is the fastest street-legal car in the world with a top speed of 431.072 km/h. Chief designer for the Bugatti Veyron was Hartmut Warkuss, while the exterior was designed by Jozef Kaban from Volkswagen. Though it was commissioned by VW, the Veyron can only be sold through Bugatti dealers.

Though many special variants and limited editions of the Bugatti Veyron were produced, all the cars are fitted with an 8.0 L W16 cylinder engine with four turbochargers and dual clutch transmission with seven gear ratios with magnesium paddles behind the steering wheel and a shift time of less than 150 milliseconds. He Bugatti Veyron can be driven in either semi- or fully automatic mode and, according to the manufacturers, its engine can produce up to 1,001 metric horsepower. In December 2010 Bugatti started to offer prospective buyers the opportunity of customizing the interior and exterior colors of their Veyron through their official website’s application called Veyron 16.4 Configurator.

Bugatti Veyron was born when in 1998 Volkswagen bought the trademark rights from the former Bugatti manufacturer wishing to revive the brand. This new Bugatti got its name from Pierre Veyron, a former Bugatti development engineer, test driver and company race driver who, together with co-driver Jean-Pierre Wimille, won the 1939 24 hours of Le Mans behind the wheels of a Bugatti. As for other specifications, car buffs may be interested to know that Bugatti Veyron’s brakes use cross drilled, radially vented carbon fiber reinforced silicon carbide composite discs which have a much stronger resistance to brake fade, with Bugatti claiming a maximum deceleration of 1.3 g’s on road tires. Yet as an extra safety feature, in case of brake failure, an anti-lock braking system has been installed in the handbrake.

A mid-engine, four-wheel drive, two-door coupe Bugatti Veyron, meaning a basic model of the automobile can cost a minimum of €1,225,000 or US $1,700,000. It can go from 0 to 100 km/h in 2.46 seconds and it needs ten radiators to cool the engine system, transmission oil and a heat exchanger for the air to liquid intercoolers. As mentioned above, the Bugatti Veyron was produced in many special variants, such as the 2006 Pur Sang of which only 5 pieces were made with high-gloss bronze roadwheels and diamond-cut glass-like finish. Other special models include the Pegaso, Sang Noir, Bleu Centenaire, Nocturne, Soleil de Nuit, Grey Carbon, Bijan Pakzad Edition, L’Or Blanc and many others.

Bugatti Veyron Pictures Gallery

Clutch replacement

Cars are very important for every one of us, and keeping them in good shape means also having a safe driving experience.

A clutch is the device that couples the engine to the drive train. It represents the mechanism for transmitting rotation which can be engaged and disengaged. A basic clutch works alongside two rotating shafts. One is usually driven by a motor while the other one is driving another device. The clutch helps in the functioning of these two by connecting them together in order to spin or to be locked together. In many cases when this mechanism doesn’t work the way it should be a clutch replacement is needed.

The car engine spins all the time, even when the wheels stop. When you try to put your car to a stop without disengaging the motor, you need to disconnect the wheels from the engine. And this is when the clutch comes in. In the clutch system the friction play a major role. Friction refers to the measure of how hard it is to slide one object over another. The amount of force that the clutch can hold depends on the friction between the flywheel and the clutch disc.

The most common problem we have to deal with regarding clutches is when they wear out. Just like in the case of brake system, friction components of the clutch system wear out depending on how often we use them. If these friction materials wear out, the clutch starts to slip and it will no longer be able to transmit power from the car engine to the wheels. So, it becomes obvious the important role of the clutch for the maximum performance of the car. It is very important to inspect the clutch parts from once in a while or every time you notice something unusual about your clutch, and to have a clutch replacement if needed. You should count your own safety and the performance that should never be compromised.

Among the signs of the clutch wear, we should mention a slipping clutch. A simple way to see if your clutch is slipping is to find a hill somewhere and to bring your car to a reasonable speed around 40 mph and then select a high gear 4th or 5th and push the accelerator to the floor. If the car’s rev counter suddenly raises with no equal sign of acceleration this is a sign of clutch wear. Another sign of clutch wear is any unusual noise. When the clutch plate has moved slightly and becomes misaligned then your car can also have some functioning problems.

And these are only a few reasons when you will need a clutch replacement to your car.