is it true that a manual transmiction is more fule efeshent than an automatic one

Yes, a manual transmission is more fuel efficient than a standard transmission (assuming of course, all details of the engine are the same). This is plainly because as a driver you have more control over the engine and you never have to put your foot to the floor and typically you can cruise at a lower rpm. Also, the gears are shorter so you stay at a higher rpm while gearing up for less time than a standard.

quote:

Originally posted by ancientanvil:
is it true that a manual transmiction is more fule efeshent than an automatic one

Is it true that people who graduated from Pre-School know how to spell "transmission"? and "fuel"? and "efficient"?

quote:

This is plainly because as a driver you have more control over the engine and you never have to put your foot to the floor and typically you can cruise at a lower rpm.

Yes and no.

Your statement is true for older manuals.

Newer autos, however, can respond much faster and more precisely than a human can. The most modern autos are actually more fuel efficient than the manuals on the same car.

There are a number of cars on the market now that get better mileage with the Automatic option with the same engines. The Toyota Corolla and Honda Civic are two that come to mind.

quote:

Originally posted by amarko:
Yes, a manual transmission is more fuel efficient than a standard transmission

Standard transmission is manual transmission, as it still comes standard on most cars. You mean automatic transmission.

Sorry about that. I did mean automatic.

Where did you find that info about the manual/automatic mpg facts? I'd like to see it.

Then you can't forget the continuously variable transmission that some companies are starting to replace the automatic option with. (I hate CVTs personally), In theory you could call one an "automatic" transmission and they are the best for fuel economy.

Automatic transmissions are less efficient than manual transmissions because they weight less, have fewer moving parts, and are connected to the engine with a rigid clutch instead of a torque converter. Obviously lighter weight is better for fuel efficiency because it takes less energy to move a lighter object. Automatics must have more moving parts and hydraulics to automate gear shifts which requires power from the engine and creates more friction causing less power to get to the wheels. Having a rigid clutch transmits power directly between the engine and transmission but a torque converter by design must slip creating wasted energy.