CVT vs MT vs AT vs AMT

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I've always owned manual transmission (MT) cars, but while living in USA I drove automatic transmission (AT) cars most of the time (manual transmission is not very popular over there).

When I recently bought a car I was offered a continuously variable transmission (CVT) that, instead of gears, uses an steel belt and two variable-diameter pulleys. The system works nicely and it may even offer a set of "simulated" fixed transmission rates. While the fuel economy is not as good as MT it gets quite close.

For many years AT cars exhibited worse fuel economy than their MT counterparts. I've always found weird that, but I am not a mechanical engineer 8but wikipedia tells me it's because of torque converter mostly). Now it seems some manufacturers, probably feeling the pressure from regulators due to the high cost of petrol, are delivering a new technology (maybe not so new) dubbed as automatic manual transmission (AMT). The good thing about AMT is that its fuel economy is even better than MT.

I'm quite sure I'm not helping you out on your next car buying decision but I hope now you're aware of the many choices available for your car's transmission.

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