What is the difference between AT and CVT?
3 Answers
There are three aspects: different fuel consumption, different advantages, and different shifting characteristics. The differences between AT and CVT: Different fuel consumption: AT transmissions consume more fuel, while CVT offers better fuel economy. Different advantages: The advantages of CVT include simple structure, compact size, fuel efficiency, and smooth operation, whereas AT boasts mature technology, excellent product stability, and the ability to transmit high torque. Different shifting characteristics: CVT provides an extremely smooth driving experience without any gear shift jerks, while AT shifts slower and the transmission consumes more power. AT transmissions have real gears, and their shifting actions occur at specific points. CVT transmissions do not have real gears and can continuously vary the ratio. The best way to distinguish them is to observe the tachometer needle during uniform acceleration from a standstill: AT transmissions show obvious upshifting actions—commonly described as the RPM rising, then dropping before rising again—while CVT transmissions exhibit a steady, slow increase in RPM or maintain a constant RPM. The pros and cons of the two transmissions: AT transmissions can provide drivers with a good driving feel, while CVT can make the car smoother and more fuel-efficient.
The most fundamental difference between AT and CVT lies in their structural design. AT transmissions contain multiple sets of planetary gears and transmit power through a torque converter, resulting in noticeable gear shifts during driving. Having driven many AT-equipped vehicles, I can confirm that even modern 9AT and 10AT transmissions, while significantly smoother, still exhibit slight power interruption during rapid acceleration. CVT operates completely differently - its pulley and steel belt combination enables continuous ratio changes, delivering electric-car-like smoothness. For daily commuting, CVT undoubtedly offers superior comfort, though driving enthusiasts might find its constant RPM during acceleration lacking in excitement. From a durability perspective, AT can handle higher torque (explaining its prevalence in off-road vehicles), while CVT offers better fuel efficiency but may experience belt slippage under aggressive driving.
I've seen all kinds of transmission issues at repair shops, and the maintenance costs between AT and CVT transmissions vary significantly. AT transmissions have a mature and reliable structure, typically requiring transmission fluid changes only every 80,000 kilometers. Even when problems arise, they're often just solenoid valve failures. CVT transmissions, on the other hand, are much more delicate. They require specialized fluids and maintenance every 40,000 to 60,000 kilometers. If you frequently floor the accelerator or tow heavy loads, the steel belt is prone to damage. In terms of fuel consumption, the same car model equipped with a CVT can save 1-2 liters per 100 kilometers, especially noticeable in stop-and-go city driving. However, last month, an old Qashqai came in for repairs with its CVT transmission chain slipping at 200,000 kilometers. Replacing the entire unit would cost tens of thousands. So, for long-term vehicle use, driving habits matter. Gentle driving makes CVT a cost-effective choice, while aggressive drivers are better off with AT.
