Automatic vs Manual Transmissions, What is the Difference

Automatic or manual transmission, which is the best option for you and perhaps the best option for your vehicle. There can be many advantages or disadvantages over either option, so in this article I will be discussing each in depth. Over the years of driving, I have been exposed to a variety of vehicles, even the same models of vehicles yet with a different transmission. In North America, an automatic tends to dominate the automotive market, while in other parts of the world a manual tends to be the more popular option. With regards to Canada, an article from The Globe and Mail states that only 9% of the vehicles offered in 2017 was only 9%. Furthermore, only 3.6% of new car buyers requested a manual transmission.

A traditional type of automatic transmission works under hydraulic principles, using fluid couplings and friction discs in order to achieve various gear ratios for speed or torque ranges. A more modern type of automatic is a CVT (continuously variable transmission) which uses adjustable drive pulleys instead of planetary gear sets. The traditional style of automatic was originally shifted manually, working up to vacuum operated shift points and eventually being controlled by a vehicle's computer. The CVT, on the other hand, doesn't have gears for forward speeds, is controlled by the vehicle's computer and the transfer of input/output ratios is seamless.

An automatic transmission tends to be the most comforting option, whether your commutes are short or long. Based on the position of the throttle pedal or engine load, the vehicle calculates what gear is best. There is no need to operate a clutch, which can be quite troublesome in stop and go traffic, especially if you are required to take off on a hill. Manual downshifting is not required when slowing down, approaching a hill, before entering a corner, or passing a vehicle. An automatic also allows you to pay more attention to the road as you are not constantly required to shift or remove your hand from the steering wheel.

As for the disadvantages, they are not always as robust as a manual, and maintenance can be neglected by previous owners as a fluid and filter replacement should be part of scheduled maintenance. Automatics don't tend to last as long mileage wise and in a pulling situation or when exposed to high horsepower can fail easier under stress. They can also be slightly harder on fuel, but this can depend on the model. From a performance standpoint, while automatics in the past tended to be more sluggish between gear changes and did not necessarily offer a wide variety of gear ratios. Automatics tend to have a 10 to 15 percent power loss through the transmission, whereas a manual would only have 5 to 10 percent power loss. However, with advancements in technology and materials, shifting transitions and power loss is being greatly reduced.

Unlike the automatic transmission, a manual is solely based on the control of the driver. The engine distributes power to the transmission through a clutch, in order to disconnect the transfer the clutch pedal is depressed. The disconnection of the transmission allows the vehicle to stop, take off from a stop smoothly, as well as change gears. In passenger vehicles, manual transmissions first started out with non-synchronized that required double clutching in order to change gears. Eventually, designs were improved, creating a synchronized transmission allowing the driver to change gears much more efficiently without double clutching.

Manual transmissions are typically the preferred option for most car enthusiasts as they can enjoy the extra connection and control over the vehicle. While it can be slightly slower in shifting compared to some of the more modern options, it doesn't appear as a disadvantage for some. Fuel economy in most manual vehicles can be improved if you are moderate with the throttle, but this doesn't apply to all vehicles. While it is rare, there is the odd vehicle which can be harder on fuel with that manual option. They are normally more robust than an automatic, can last much longer mileage wise, and is able to withstand higher power outputs. Oil replacement maintenance is also extremely important with a manual transmission, yet the risk of damage or failure maybe marginally lower as there typically isn't a filter to become plugged, no shift solenoids to stick, and no hydraulic pressure that would affect shifting. Even with that reduced risk, oil can still break down through heat and age eventually reducing lubricating qualities and creating component failures.

Just like the automatic, the manual transmission does have it's drawbacks too. As mentioned above, shifting times can be slower compared to some of the more modern automatic options. Depending on component failures or worn parts, a manual transmission can be more expensive to rebuild than compared to an automatic. Clutch replacements can be costly and frequently required if a driver is not well skilled. I have seen clutch replacements required at 100,000km, while other vehicles lasting to over 400,000km with the original clutch. And probably the biggest disadvantage is the manual being somewhat of an inconvenience for some drivers. With an automatic, you can put the car in gear and go, while the manual requires operation of a clutch and shifter. For me, driving a manual has become second nature, but I will admit stop and go city driving can be an annoyance at times.

Between which choice of transmission is best for you, it depends on what your application will be, what type of vehicle you have, and the experience you are seeking. Not all automatics operate the same and that principle applies to manual transmissions as well. Sadly as seen with the statistics above, the manual transmission is slowly demising amongst automotive ownership. Personally, I enjoy having a daily driver manual vehicle and as mentioned above it is second nature to me. Hopefully, with the information I have provided will assist in your purchasing preference or even just feed your need for information.