I'm having a discussion with a guy on another forum regarding cars with automatic transmisions.

He says a car can brake quicker if the driver shifts into neutral. In order for this to be an "automatic" reaction in an emergency, he says drivers should shift to nuetral every time they brake to a stop.

I say:
1. If there is ANY decreased braking distance it is negligible.
2. I don't think it is safe for auto drivers to be shifting in and out of neutral. Even for experienced drivers.

What do y'all think? I need some more ammo to throw at him besides "Is not!"

A third question is wear and tear on the tranny. Is there more, less, or no difference in wear?

 

Also one thing, at least in Canada, cruising in neutral is illegal.

 

Absolutely wrong. In theory - no difference. In practice, when in gear, you get better "power" braking since "power" gets energy from engine (rpm dependent). Difference is hardly noticeable in modern cars. Changing to neutral takes effort, time and drops your concentration from a precise braking. Don't do it.

 

Well, i know for sure that if you get in a pretty bad accident the engine's damage can be reduced if in neutral. Going in and out ill most likely reduce transmision life, especially if you drop it back into D ith the revs higher than idle, kind like neutral dropping. I ould think that without the force of the car going foward though, neutral would seem to help a little but the power braking theory does sound legitimate.

 

Yea, power brakes get their power from the engine. I forgot about that. I don't know how much difference there is between idle speed in neutral and RPM under braking.