got this from another site.
1.
Acceleration. A manual transmission accelerates more rapidly, and evenly throughout the gears, especially in a situation where one needs to merge into traffic more quickly. Automatics, on the other hand, start off very slowly in the lower speeds, then accelerate more in the higher speeds. This makes it very difficult to predict just how long it will take to reach the targetted speed. Score 1 for the manual transmission.
2.
Maneuverability. Due to the acceleration differences above, an automatic is less maneuverable in a crisis situation (say, quick lane changes when being cut off), whereas a manual is just as peppy as its owner. Advantage: manual.
3.
Assistance in maintaining alertness. Since one is constantly shifting gears in a manual transmission vehicle as traffic speeds change, one is forced to stay alert. This is especially important in stop-and-go traffic situations, where the car can stall if one isn’t alert. Automatics on the other hand, require no adjustment or attention, as the correct gear is always engaged. In a traffic situation, this could cut down on one’s alertness. This is especially dangerous when dealing with erratic drivers who will change lanes without signalling in tight quarters or any of the other myriad hazards such as rear-endings that come with thick traffic. Advantage: manual.
4.
Fuel efficiency. An automatic guzzles far more gas than a manual vehicle-- EPA statistics and ratings on fuel efficiency show exactly that. This is because some energy is used to power the gear-shifting mechanisms in an automatic vehicle. A manual transmission requires none of that energy, since the driver does all of that him or herself. Advantage: manual.
5.
Calorie burning. An automatic requires the actions of only one bodypart, the right leg, alternately pressing the gas pedal or brake, and maybe the hands for some occasional steering. A manual transmission, on the other hand, requires the use of both legs, with the left leg engaging the clutch as necessary, the left arm constantly steering, while the right arm shifts gears. The right leg is used in the same manner as the automatic. So, driving a manual transmission is more of a workout than driving an automatic. Advantage: manual.
6.
Wear on brakes. When going downhill, in an automatic, one must constantly keep riding the brakes. In a manual transmission, on the other hand, one merely needs to shift into a lower gear, and with minimal useage of the brakes, one’s speed can be controlled quite easily. This girl noticed a huge difference the first time she had to go down the other side of the Santa Cruz Mountains-- she merely downshifted to third gear, and her speed was very controlled, while she saw continuous brake lights and smelled burning brake pads from the automatics all around her. Advantage: manual.
7.
Startup due to battery failure. In an automatic, a jumper cable and additional vehicle are required, to restart a car with a depleted battery. On the other hand, one merely needs to push a manual transmission vehicle, and get it going at a reasonable speed, then jump in and start the vehicle-- it will start up with no problem, and the battery will recharge as it is driven. Advantage: manual.
