The automatic gearbox has numerous different names. Volkswagen VAG manufacturers, SEAT, Skoda, VW and Audi all name it DSG, known as direct shift gear. Porsche will sell you a PDK gearbox. Several manufacturers also offer a CVT gearbox, another variation that complicates things even more. In the past, automatic gearboxes were more often found in larger, more expensive luxury cars. Today, buyers can specify an auto in everything from the budget city car, to the best-selling small hatchback and beyond. But an automatic gearbox often add to the price of a new car. Is it more luxury not having to change gear all the time and cruise to your destination. It’s all down to personal choice whether the driver wants to have full control of the vehicle, when people say “I want to feel part of the car.” Bear in mind, some people only have a driving license that permits them to drive automatics only. Let’s delve into this further and see the good and bad points for both gearboxes.
Many vehicles have a manual gearbox in the U.K. You may notice, many cars at the 'affordable' end of the market have a manual gearbox as standard, while many enthusiasts prefer this type of transmission even when buying an expensive sports car.Keeping up to speed in today’s world, manual gearboxes have six forward gears, known as a 6 speed in place of five or, just a few decades ago, four. Some of the high-end sports manual cars even offer seven gears. Both Porsche and Aston Martin are examples of this.
Enthusiasts for manual gearboxes tend to enjoy controlling the car, as only you can choose which gear to use. This can provide more driver involvement, giving the feeling of a direct connection between human and machine, with a mechanical feel to each gear change, instead of a computer taking care of it for you. A prime example for a better feel is when using a manual gearbox for towing and off-road driving, where you want to hold a low gear. On the other foot, this also means a manual requires more effort than an automatic, which becomes most apparent in heavy traffic. Some learners also find the added complication of gear selection and clutch control scary and take their driving test in an automatic vehicle.Some car makers are moving away from manuals, offering an automatic as standard on some of their models or with some of their engines; this is often for reasons of economy, as the latest dual-clutch and automatic gearboxes can help cars use less fuel and produce less CO2 than those with a manual transmission.
Automatic gearboxes have been around for 7 decades. Within that time there has been many upgrades and designs, along with many software updates, the general working rule of how they work remains the same. You select from Park, Neutral, Reverse or Drive, known as P, N, R and D using a gear lever, control knob or occasionally buttons. On choosing a gear position, hi-tech electronics, coupled with a hydraulic ‘torque converter’ clutch, select and engage the correct gear. Changes up or down through the gears are handled by this hydraulic clutch, which is essentially a fluid, spun at speed, that makes the connection between engine and gearbox. The use of hydraulic transmission fluid makes for very smooth changes and explains why traditional automatic gearboxes .A lot of automatic gearboxes let you change gear manually, through the gear selector lever or paddles mounted on the steering column. This is sometimes referred to as a 'semi-automatic' mode.With improved technology and software updates, automatic gearboxes are becoming increasingly complex as well as featuring more and more gears. This allows the engine to run at its most efficient point for more of the time with the aim of reducing economy and emissions.
Many people like automatic gearboxes for the convenience. You can select the car in D and forget about touching the gear lever until you want to park or turn around: there’s no clutch to bother with, either. Most drivers find that traditional automatic gearboxes offer a very smooth driving experience.Cars fitted with automatic gearboxes can sometimes use more fuel than the same model fitted with a manual, although the reverse is also true in some cases. Vehicle emissions can also be lower with an automatic gearbox too, which can lead to a lower Benefit-in-Kind company car tax banding – worth bearing in mind for company car users. Enthusiastic drivers might find that a ‘self-shifter’ offers less control – you might occasionally find yourself in a higher gear than you’d ideally want to be when taking a corner, for example.
Dual-clutch gearboxes seem to offer the best of all possible worlds to the modern driver: they provide the convenience and ease of a conventional automatic plus the control and engagement of a manual, should you want it. Dual-clutch gearboxes also usually manage to be more economical than either a traditional automatic or a manual, with better performance. There are, however, things to be wary of.The main question with dual-clutch gearboxes is one of expense. These gearboxes usually cost more to buy and they can be rather expensive to fix if they go wrong and your car’s warranty has expired. The Dual clutch gearbox can feel more aggressive than smooth compared to the standard automatic gearbox.
A CVT gearbox essentially consists of two cones connected by a very strong belt or chain, which gives rise to its nickname of a ‘rubber band’ gearbox. As the cones move closer or further away from each other, the belt gets slackened or stretched. The ratio between how fast the car’s wheels are turning relative to the speed of the engine alters as the cones move.
A CVT gearbox offers a very smooth driving experience, as there are no ‘gears’ to engage or disengage, just a continually moving belt. CVT gearboxes are relatively cheap to build and can offer good fuel economy. The newer Hybrid vehicles tend to use CVT technology, as it’s easy to bring together with their complex powertrains and the combination of electric power and a CVT gearbox is usually a good result.But the CVT gearboxes can lead to a very noisy driving experience, as the engine is sometimes held at high revs while the cones move into their ideal position.
The electric cars tend to use motors that don’t require a gearbox. Electric motors can offer instant power, but their operation is totally different from internal-combustion engines. As electric and hybrid technology advances, the line between motor and gearbox is likely to become ever more confusing, so keep an eye out for what the future holds.
9th of October 2019