Automatic transmission (AT) is a type of vehicle transmission mechanism that can automatically shift the gear of a vehicle as it moves without the driver bothering to change the gears manually like in manual transmission. In order for the gear to handle the speed range and torque outputs, the system adjusts to the rotational speed of the internal combustion engine. The phrase “4 speed” is actually referring to the number of gears that this transmission system can shift into during operation.
Above are some knowledge of how a general automatic transmission operates inside your car, Naijauto.com now brings to you the basics of 4-speed automatic transmission in vehicles.
4-speed automatic transmission – What does it mean?
Each gear you see in a gearbox actually represents a fixed speed range in that system. So, for a 4-speed gear system, you can guess that such a vehicle can only move between some fixed set of four-speed range and RPM. A transmission is generally such a complex mechanism that allows an engine to run at diverse ranges of speed. As an example, at a 1,000 RPM, it allows the vehicle to run at 60, 45, 20 and 10 km per hour.
It will let the car run at that RPM for those four different speeds because it is a 4-speed transmission. And if it was to be a 6-speed transmission, then it will run at 6 different speeds at that RPM range. Because a 4-speed transmission has to cover more speed (kph or mph) before shifting to the next gear, it will generally accelerate slower than a 6-speed transmission in the same car of the same model.
A 4-speed automatic transmission gearbox (Internal mechanism)
The 4-speed transmission automobiles were actually manufactured during the 90’s but currently, you are more likely to find either 5-speed or 6-speed transmission in vehicles you see around you. These car models; Mazda Demio, Subaru Forester, Scion xB, Dodge Avenger SE, and many others were actually some of the best 4-speed transmission powered automobiles that were produced. Also, when it comes to popular brands, Toyota has some three popular models – Yaris, Tacoma, and Toyota Corolla - that had this 4-speed transmission in some cars within their line.
Automatic Transmission, how it works?
5-speed transmission vs. 4-speed transmission – Which is better?
We cannot and will not make a general assumption that one is better than the other, rather we will advise that you consider some crucial and differentiating factors like the vehicle’s model, brand, and year of production, among many other factors before you decide. Otherwise, your comparison might end up showing not much difference between these two.
Nonetheless, we will highlight some of the benefits you will surely be getting in a 5-speed auto transmission fitted vehicle:
- You will enjoy better fuel economy because of its narrower speed range
- The shift will feel better to handle because it will involve less speed change compared to a 4-speed type.
- It will actually give you more actuation overhead energy and shifting clutches. And if you continue to take that advantage frequently, you will definitely have horrible fuel efficiency in the end.
- Without any doubt, better drivability will be enjoyed in the 5-speed transmission.
A 2010 Honda Civic LX-S Sedan has 5-Speed Automatic Transmission
Considering financial sense, it might be really advisable to go for a 4-speed transmission as it will generally be lower in price compared to a 5-speed transmission. And as a matter of fact, there wouldn’t really be a huge visible difference in performance and fuel efficiency when comparing these two transmissions.
The major thing that will be noticed is that the presence of more gears in the 5-speed transmission will enhance its speed and performance while a 4-speed transmission will lag a bit behind in terms of road performance. Another thing to keep in mind is that the 5-speed transmission will require more maintenance and cost.
So, we will conclude by coming out plain that, a 4-speed transmission vehicle is a good choice for its cost. Although many auto experts may give you a different opinion, we believe that, if you are buying a low budget and you naturally don’t even fancy over-the-top kinds of stuff, then please just go for a 4-speed automatic transmission. But if otherwise, then go for a 5-speed automatic transmission or higher.
>>> Check out these other interesting posts on Naijauto:
- Diesel engine vs Petrol engine – Which is best for you?
- Are CVT transmissions reliable in a long term?
- Automatic transmission vs CVT: which one is better?