I drive a 5-speed stick shift and would like to know if it's best to shift the car in neutral and release the clutch while at stop signs, red lights, etc? Also, is it ok to shift the car in neutral and coast down hills?
Finally, some people shift from 5th gear down to second, or even 1st as they slow down. Is this really necessary? Or can you simply shift the car into neutral and coast to a stop?
We'll start with the sitting-at-a-light scenario. Yes, if you are going to idle for more than a few seconds, go ahead and put the transmission in neutral and release the clutch. This will rest the clutch plate diaphragm, the release bearing, and your left foot.
When proceeding down steep hills, as with an automatic transmission, it's always a good idea to downshift and keep the vehicle at a desired speed with the use of "engine braking", as opposed to the brakes themselves. Riding the brakes on a downgrade for long periods of time will overheat the brakes and cause brake fade, which can be dangerous.
When slowing to a normal stop, downshifting is really a personal preference, and it is fairly safe staying in neutral and simply using the brakes. Personally, I downshift through the gears in order to keep the transmission in a gear range to match the speed of the car. This way if immediate acceleration is called for you simply hit the gas pedal, as opposed to depressing the clutch, downshifting, releasing the clutch, and then hitting the gas. This method may put more wear and tear on the clutch, but it might get you out of a tight jam.