Alberick

First, sorry if this is the wrong forum. Mods, feel free to move.

I have a question concerning an automatic transmission. I regularily drive a Daihatsu with an a/t on a long stretch of highway (approx 120km) and there is a section where it's going downhill for about 8 km.
I usually select position N on that stretch and just let the car roll downhill if theres nobody around.

Is it right to do that or could this damage the transmission?

Thanks,

Ramon

Graz

For one thing it's dangerous, no engine braking!

Should "roll" even in gear. The electronics will shut down the fuel flow if the throttle is closed so you won't be using any fuel. In fact by putting it in neutral you use more fuel to keep it idling.

Alberick

Thanks a lot for the tip.

I know it could be dangerous, but when I drive this long downhill stretch it's usually 11pm and there's nobody around so I though fuel consumption would slightly go down if I keep it rolling in N position.

Well, let me give some details about the car it's a Daihatsu Cuore 0.9 3-cylinder enigne, the a/t has 3 gears so when your drive like 120km/h you're at about 4900 rpm. reason why I believed that by doing this, it would a) save fuel and b)less stress on engine internals by letting it roll in idle.

But, of course if i''m wrong with my assumption, no need doing that anymore...

Ramon