There are two basic types of vehicle transmissions namely; manual, and automatic transmission. However, the year 2003 via a PS2 video game – Need For Speed (Hot Pursuit II), was my first rendezvous with vehicle transmission other than the conventional “manual”, and “automatic” transmission – to which the latter was really starting to catch on back then as more and more vehicles being brought down to Naija were mostly Japanese models – from America and were almost exclusively automatic transmissions. This clip at 1:10 from xTimelessGaming:
https://www.youtube.com/watch?v=L2f2aJFJLck fully illustrates what I’m going on about. Coincidentally this version of NFS didn’t only pique my curiosity towards automobiles but also really compelled my first true foray into rock music as the soundtrack to this game is surely a classic and upon listening to any of them or watching throwback in-play clips (still had the poster from the PS2 pack “plastered” on a wall in my childhood bedroom until it was removed just recently) such as the one posted; immense nostalgia hits, like an avalanche…

Well, that’s that – let’s get back to the topic at hand, shall we – transmission. If you didn’t already know, vehicle transmission systems play a crucial role in ensuring not only smooth but efficient power delivery from the engine, to the wheels. Whether you drive a manual or automatic transmission vehicle, understanding the basics of how these systems work can help you appreciate the intricate mechanics behind your car’s performance.

Manual Transmission

Manual transmission, also known as “stick shift” by those across the Atlantic, requires the driver to manually engage and disengage gears by stepping on the clutch and adjusting the gear lever to different positions depending on the driving conditions as much – if more, or less speed is required. The key components include:

Clutch: Located between the engine and the transmission, the clutch allows the driver to disconnect the engine from the transmission temporarily. Pressing the clutch pedal disengages the engine, enabling gear changes.

Gears: Manual transmissions have multiple gears, typically arranged in an H-pattern albeit some racing cars have theirs arranged in a dissimilar pattern called “Sequential Manual” – where you have go through one gear to get to the next by pushing the gear lever upwards to drop a gear e.g. from 3 to 2, and move up a gear e.g. from 3 to 4, by pulling the lever backwards – with the movements repeated to get to the desired gear of choice which makes for a faster shifting time evidently required in tumultuous racing environments. Each gear provides a different speed and torque ratio, allowing the driver to adapt to varying driving conditions.

Transmission Input Shaft: Connected to the engine, the input shaft receives power and transfers it to the gears, determining the vehicle’s speed.

Output Shaft: Connected to the wheels, the output shaft transmits power from the gears to drive the vehicle.

Shifter: The driver uses the shifter to select the desired gear, determining the speed and efficiency of the vehicle.

All these culminate to one of the most entertaining experiences ever as “true gear-heads” will tell you! Pressing on the clutch and going through the gears makes for a more engaging drive. However, due the “labourious” nature of it all – manual transmission is becoming extinct, unfortunately. The good people at Engineering Explained already did a wonderful job “explaining” the basic process here:
https://www.youtube.com/watch?v=8VEc3zhGaro

Automatic Transmission

Automatic transmissions greatly simplify the driving experience by automatically changing gears without any driver input or intervention. Key components include:

Torque Converter: Replacing the manual clutch, the torque converter is a type of fluid coupling which is used to transfer rotating power from the engine to the transmission, allowing for smooth gear changes.

Planetary Gear Set: Instead of a manual gearbox, automatic transmissions use planetary gear sets to achieve various gear ratios. These gear sets automatically adjust to provide the optimal combination of speed and torque.

Hydraulic System: Automatic transmissions rely on a hydraulic system to control gear changes. Transmission fluid is pressurised and directed to engage or disengage clutches and bands, facilitating smooth transitions between gears.

Transmission Control Unit (TCU): The TCU monitors various factors such as vehicle speed, engine load, and throttle position to determine when to shift gears. It uses this information to control the hydraulic system and ensure optimal performance.

Shift Lever: While automatic transmissions don’t have a clutch pedal, they have a shift lever that allows the driver to select between Park, Reverse, Neutral, Drive, and other gear options.

I’d like to believe most of us are quite familiar with this process already as it is quite common. You press down on the accelerator pedal to move, the brake to stop or slow down, and simply steer. There isn’t that much to it.


Please note: As mentioned in the beginning of this article the two basic types of transmissions are Manual and Automatic, anything in-between such as iMT (Intelligent Manual Transmission), CVT (Continuous Variable Transmission), DSG (Direct Shift Gear-Box) or DCT (Dual-Clutch Transmission) can still be classified under either one of them. For me personally, the presence of a clutch pedal denotes the answer as to whether it is a manual, or an automatic transmission.

Understanding the intricacies of manual and automatic transmission systems however, provides insight into the coordination required to optimise a vehicle’s performance. Whether you prefer the hands-on engagement of a manual transmission or the convenience of an automatic, both systems are designed to enhance the driving experience and maximise efficiency. Thanks once again for reading.

https://autohub.ng/blog/how-vehicle-transmission-systems-work/