If that CVT is poorly designed then it probably is, along with no widespread knowledge around them. Knowing this, CVTs are usually recalled and have had plenty of issues, such as Nissan and Subaru.(8)(9) Are they expensive to repair? Probably yes. They are also controlled by the car’s ECU, so if the ECU is programmed poorly, then the CVT will behave weirdly. They’re flimsy if you think about it, so, they usually have some sort of fault due to them being under-engineered. The biggest problem with CVTs is that they aren’t sporty nor beefy. Most hybrid cars use CVTs because they can make them work synchronously with the electric motor. Nissan uses CVT on most of their vehicles. There are many manufacturers who use CVTs for a good while already. If the engine can run as efficiently as it can, then it pollutes less. Weird, I know.(7)ĬVTs are starting to become increasingly common, due to fuel efficiency and pollution regulations. Some manufactures create fake gears shifts so people aren’t disturbed that their car doesn’t shift gears. My transmission shifts gears and I have a CVT, is this normal? Yeah, believe it or not it’s normal. If you barely accelerate and you feel a jolt, the belt is likely used and almost ready to fail.(6) Artificial Gears When the belt settles the RPM also has to settle, which happens with a jolt. If it stretches a bit, it can come off the bobbins slightly and effectively slip a bit. As such, if you use a bit too much force on a belt, as in a brisk acceleration, the belt will stretch a bit. Even if it’s a metal belt, it’s still a belt. Why does my CVT sometimes jolt? Well, as I stated a bit ago, a CVT uses a belt. It’s the point where your engine is the happiest. The RPM you’re hearing from the engine is actually engineered to be like that. However, a car with a CVT doesn’t have a redline, and the constant RPM you’re hearing is far from that redline. If it stays at redline for multiple minutes, you will break the engine. The redline is the point where the engine can start damaging itself, due to heat and stress. They also drive like an automatic, so no need to shift gears.ĭoes that hurt the engine? No, you shouldn’t be worried at all. They can constantly use the engine as efficiently as they can. This is what causes the CVTs to be so efficient. Likewise, it will constantly stay at max power RPM because that’s the fastest way it can accelerate. It’s a similar story with accelerating as fast as you can. That’s why a car with a CVT stays at a constant RPM and doesn’t shift gears. Below the RedlineĪ CVT fixes the problem, because it will always stay around the max torque RPM when cruising, regardless of speed. If you’re too slow in 3rd gear at max torque RPM and you shift gears to get to what speed you need, you won’t be at that RPM anymore. However, a regular transmission can’t do that. An engine runs the most efficient around its max torque RPM(5), so it would be in the car’s best interest to run at max torque. This behavior comes with a few distinct features, such that a transmission can use the engine as efficiently as it can. CVT comes from a Continuously Variable Transmission, because it can change its gear ratio constantly, within a range of the 1st gear and last gear. A CVT uses a belt which wraps around two sort of bobbins which can, in fact, change their size(4).īy changing their size, they can change how much or how little the engine RPM is divided. Seeing how you can’t change the cogs’ size you have a certain number of fixed gears. In a regular transmission, each gear is made of 1, 2, or 3 pairs of metal cogs which are meshed together (even if it’s a manual or automatic, the concept is the same)(3). Or, in fact, it has an infinity of “gears”. To understand how a CVT works, you need to understand how a regular transmission works, because a CVT doesn’t have any gears. How a CVT Transmission Works The Subaru Legacy sends power to all four wheels utilizing a CVT.
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