Much has been said about which is the more superior transmission in a car: manual or automatic. Just to confuse things, there has been an infusion of fence-sitting pretenders, like semi-automatic, Tiptronic, sequential manual and the weird CVT (Continuously Variable Transmission), which fall in the wide gap between fully manual and fully automatic power trains.
While it might seem difficult to place the call on which outranks the other, it is easier to break the argument into four separate sections from which judgment can be made: mode of operation, driveability/usability, performance and economy.
Mode of operation
The transmission of power in a car starts from the engine, which is mated to a flywheel —a heavy, toothed metal disc that acts as part of the starter system. The starter is engaged to this flywheel, which then turns the engine every time it is cranked.
The flywheel also damps engine vibrations for increased smoothness. Onto this flywheel is bolted a clutch, which is then connected to the vehicle gearbox. The difference between manual and automatic gearboxes starts from the clutch.
Manuals always use a friction clutch, while automatics use either an electronically operated friction clutch or a fluid clutch, also called a torque converter (these clutches will be explained in a later article).
The gearbox layout is the next big difference between these two transmission types. Manuals use constant mesh gears, sometimes with synchroniser assistance, while automatics have epicyclical gears.
So, how is a manual gearbox operated? The driver is supplied with three foot pedals: the throttle/accelerator pedal, the brake pedal and the clutch pedal. The clutch is the one we are most interested in.
When taking off, with the engine running, the driver is required to depress the clutch pedal, shift the gear lever into first (commonly called Gear One), then throttle up slightly while slowly releasing the clutch pedal.
At the biting point (the point where the engine power starts being channelled into the gearbox via the clutch), the driver releases the parking brake (commonly referred to as the handbrake) and motion is achieved.
As the engine revs rise, one is required to gear up, done by taking the right foot off the throttle, fully depressing the clutch pedal with the left foot, engaging the second gear with the lever, then releasing the clutch pedal while throttling up again.
This is repeated until the top gear is reached. Gearing down is done pretty much the same way.
Things are a lot simpler with an automatic. The gearbox has four distinct positions: P (Park), R (Reverse), N (Neutral) and D (Drive).
Taking off simply means sliding the gear lever into D, disengaging the parking brake and flooring the throttle. All the clutching and declutching is done for you, as is the case with gear changes, hence the label automatic.
Driveability/Usability
As explained above, driving an auto is dead simple. In D, acceleration is simply achieved by increasing pressure on the accelerator pedal, while slowing and stopping only requires a firm shove of the brake pedal.
With a manual, things are a little bit more involved than that. Downshifts and upshifts require clutch control by the driver, while a dead stop will call for further clutch control.
I tend to disagree with some of your points, but i also agree with others. Traditional auto boxes were slower yes, but there have been improvements over the years which have made them faster. For example, the dual clutch gearbox (which is auto) is faster than its counter manual gearbox. Found in golf gti and other vw group cars. Formula one (a sport that spends millions to go fast on track) uses a dual clutch gearbox cause they are faster than manual. Also the cvt gearbox, is more economical than a manual. Has less parts and ‘infinite’ gears. So times have changed. About driving a manual being enjoyable on open roads aint necessarily true. On open road, you are usually on top gear (5th or 6th) and so long as the road is fairly flat and no traffic, there is no need to change gear. I drove a manual once from that forest in limuru to westlands, without changing a gear. So was like auto, gas and brake pedal only.
Dont get me wrong, i prefer manual cars, i have had manual cars for sometime now. I prefer them not because they are economical, but because of the feeling i get when i shift, especially overtaking. In the morning when am fresh, i prefer a manual car, but in the evening when am tired, i sometimes usually wish it was an auto. Come morning the following day, am like ‘what was i thinking, manual is good’.
Morning manual, evening auto. I totally concur!
I prefer my manual ride because of the responsiveness and ability to up and down-shift. The sluggish response is what kills me on an auto tranny. However, I have not driven a sports car with auto so I am not going to blanket condemn…just yet
What about the VW’s DSG? autobox more responsive than a manual…