There used to be only two transmission choices: manual or automatic. Recently, the continuously variable transmission (CVT) became a popular third option. With automatics and CVTs competing on today’s market, a cvt transmission vs. automatic transmission comparison can help you choose which is right for you.
What is an automatic transmission?
An automatic transmission cycles through a car’s gears without any driver input.
An automatic transmission handles all of those tasks automatically. While more expensive than the standard manual transmission, the automatic was a sales success because of its convenience. Through the decades, the automatic transmission gained more gears for fuel efficiency, quicker shifts for better acceleration and computer controls for better shift quality and reduced emissions.
How do automatic transmissions work?
An automatic transmission uses hydraulic pressure to change gears. Connected to the vehicle engine, a rotating engine crankshaft transfers spin to the transmission’s torque converter. This is a doughnut-shaped metal cylinder containing automatic transmission fluid. When the engine spins the torque converter, the fluid inside acts as a torque amplifier, dampens vibrations and allows slip between the engine and transmission like a traditional clutch.
The torque converter spins an internal turbine, which connects to the transmission’s first gear. The planetary gear reduces spin speed while increasing torque and sending that motion to the wheels. Different gears are engaged by hydraulically actuated bands and clutches. A transmission fluid pump provides the pneumatic pressure for gear selection.
What is a CVT?
CVT stands for continuously variable transmission. CVTs are similar to automatics in that they operate with little driver input. Start the engine, shift to drive, and off you go.
CVTs tend to be more efficient than automatics. The average automatic is 86% efficient, meaning all but 14% of the engine’s power makes it to the wheels. CVT efficiency depends on the design, with most being 88-93% efficient. For the vehicle owner, this means lower fuel costs.
How does a CVT work?
As the name suggests, a CVT does not operate with a fixed number of gears. Instead, it has infinite gear ratios. Picture two adjustable diameter pulleys, linked by a metal belt or chain instead of gear teeth. One pulley is connected to engine power while the other is connected to the driveshaft sending power to the wheels. As one pulley expands in diameter, the other contracts, making whatever ratio the vehicle needs in that instant. Instead of shifting to fixed-size gears and their limitations, the CVT pulleys adjust diameter infinitely, and the gear ratio, as needed. The CVT advantage keeps the engine in its powerband while accelerating and lower in the RPM range for maximum efficiency while cruising.
CVT transmission vs. automatic
Now that you know the difference between an automatic and CVT transmission, let’s break down the pros and cons of each.
Pros of automatic transmissions
The automatic transmission isn’t necessarily inferior just because it’s the older technology. Here’s why automatics are still a popular choice.
There’s something to be said for being the dominant transmission choice of the last several decades. The automatic transmission is what most drivers are used to, and they know how to use one.
Manufacturers have nearly perfected the automatic transmission. Even brands that score poorly for reliability in Consumer Reports have automatic transmissions that stand the test of time.
- Plenty of mechanics to work on them
Looking for a mechanic to work on an automatic transmission? Odds are you can find one nearby. Now do a Google Maps search for nearby CVT mechanics. May the odds be ever in your favour.
- Quick shifting
Sluggish slush box automatic transmissions are relics of the past. Modern autos can shift faster than you, even if you’re champion drag racer John Force.
Cons of automatic transmissions
Though popular and effective, automatic transmissions have their weaknesses.
- Less efficient
Modern automatics get fewer kilometres per litre than equivalent CVT-equipped vehicles. If a car is more than 20 years old, even a manual transmission will offer better fuel economy. If efficiency is your primary concern, automatic transmissions aren’t the best choice.
- More expensive maintenance
Transmissions are mostly sealed units that need no maintenance for their average first owner. But what about the second owner? Transmission fluid needs to be changed occasionally, and an automatic has a lot more of it.
- More expensive to purchase
If you’re shopping for new or used vehicles, you might have noticed some models still offer a manual transmission on the base trim level. This is where the “standard” nickname came from, with an automatic as a higher cost option.
Pros of CVTs
CVTs have some advantages over automatics and manuals. They’re gaining in popularity for a reason.
- High efficiency
Looking to save some cash on gas or not go to the gas station so often? The CVT is the way to go. With higher efficiency than an automatic, you’ll notice increased fuel efficiency.
- Lower emissions
Save the planet while saving money. A CVT-equipped vehicle emits fewer emissions per mile, making it the eco-conscious choice.
- Works like an automatic
Can you drive a car with an automatic transmission? Then you already know how to drive a vehicle with a CVT: Put it in drive and go. No driver training or adjustments needed.
- No shifting
Do you get annoyed by the drop in RPMs when the automatic transmission shifts? If you drive for a rideshare company, your passengers will appreciate the CVT’s smoother acceleration.
- The latest tech
Did you just trade in your year-old phone for the newest version? If cutting edge tech is your thing, look at CVT. This is the transmission of the future (and today), and it will only get more popular.
Cons of CVTs
Not everyone is a fan of the CVT. Here are a few of their arguments against this type of transmission.
- New and unproven reliability
Reliability is a big factor in new vehicle purchases, which makes sense because vehicles cost a lot of money and you probably need yours for many years. If so, maybe skip the vehicles with a CVT. Consumer
- Unusual driving feeling
To some, driving a car with a CVT feels more like operating a golf cart than a passenger vehicle. There’s a steady hum of acceleration as the car increases speed. Some drivers prefer the reliable cadence of the engine’s RPMs rising and falling as the transmission works through the gears.
- Not available in all vehicles
Want a CVT but also want a truck? You’re out of luck. Same goes for sports cars, muscle cars and many large sedans and luxury cars. Current CVTs are designed for smaller engines with less horsepower and torque, meaning they aren’t found in several vehicle classes.
- Belts can wear out
The belt running between pulleys inside the CVT transmission is under a lot of stress and can wear out prematurely. This causes the belt to eventually snap, heavily damaging the transmission internals, and often leads to a full transmission replacement.
- More expensive to repair
CVT repairs take longer, which in turn adds labour hours. In short, CVT transmissions are more expensive to repair than a traditional automatic.
CVT vs. automatic: The bottom line
The CVT vs. automatic debate is a matter of your priorities as a driver. If you demand every last drop of fuel put to efficient use, get the CVT. If you plan on keeping your next vehicle forever, look to the lower maintenance costs and longevity of the traditional automatic. Either way, both transmission systems will be fine to drive in everyday traffic.
Nelson Xavier Ssenyange
Germax Autos, Spares & Garage Ltd
Lukade Road, Naalya