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This is not with the intention of saving fuel (as I have seen many answers assuming savings in fuel while doing this). But I have this habit of putting the vehicle into neutral before approaching stops (red lights). The main reason behind doing this being, is to reduce the strain of holding the brake pedal.

One of my friends is arguing that it's not good for the transmission system, shifting the transmission from D to N while the vehicle (with automatic transmission) is moving. I couldn't agree with him, as I couldn't find any issues with this. Also I couldn't find any information regarding the same on the manual for Toyota Corolla.

Do you guys have any technical details about this?
Thank you in Advance.

Rafi
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Being in Neutral or Drive should have negligible to no effect on the distance the vehicle travels when the accelerator is not pressed because the torque converter disengages the engine below predetermined RPM levels.

However, if you somehow were to push just a little too hard and sent the transmission into Reverse instead of stopping in Neutral, you would most likely be faced with purchasing a new transmission.

Update:

Rafi: If, by your question, you mean to say that you put the transmission into Neutral while waiting at a stop light, then this would not harm the transmission in any way.

Though it will not harm your transmission to shift into Neutral while your vehicle is in motion, the additional wear on your brakes by leaving the transmission in Drive will be negligible over the life of the brake pads. It is that minor.

jp2code
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NEVER, EVER go into neutral while slowing down to a stop, for 3 reasons: 1. You lose the added benefit of engine braking if the car's not in gear 2. If you have to quickly avoid something by accelerating and moving out of the way, you'll hit the gas and won't go anywhere 3. If the light turns green before you come to a complete stop, you'd have to go back into drive while moving. And you should only go into drive when stopped, really, really bad things may happen to your transmission if you shift to drive while moving.

John
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I do this quite a bit, actually, and I don't think there's any difference in shifting from drive to neutral when the car is moving or stopped. The reason is that the torque converter is hydraulic, so it gives you transmission some slack in order to let it shift, just as if you were pushing on a clutch. The shifting cannot possibly put more wear on the trasmission that the transmission shifting between 2 and 3, for example, something that it does thousands of time in one year.

P.S. The reason I shift into neutral at stop lights is that my car vibrates quite painfully when in drive and stopped. I haven't been able to figure that out yet, but that's another post.

vlsd
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To provide some extra information...

My wife's Subaru Impreza (CVT) shifts itself into neutral after the car has been stopped for more than a couple of seconds. You can see it go out of gear when the tachometer drops a hundred RPM or so. As soon as you take your foot off the brake, it shifts back into drive and the car is ready to move.

It also stays in gear as long as it can when braking. This gives you the benefit of engine braking while gaining the lower wear and lower fuel consumption of being in neutral.

Interestingly, the manual specifically states to not move the car while the transmission is in neutral, as it can damage the all-wheel drive system. I don't understand the reasoning behind it, but to say that coasting in "N" is fine is not correct for all vehicles.

Spivonious
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No, Not at all. Someone said here this:

"You lose the added benefit of engine braking if the car's not in gear"

Not true for automatic gears. Transmission still will allow the power from engine to go to wheels. Putting in Neutral will cut the power immediately and shorten the distance you need to come to a full stop. Try stopping from 40 mph with and without putting in neutral. You will even feel the car slowing down a lot faster in neutral.

This might be very helpful if you are speeding on highway and need to stop as short as possible, or in fully stopped/stopping for traffic like red a light.

I doubt putting in Drive harms the transmission because at all. in fact it might be less harmful than putting in Drive when fully stopped because car will not need all the power to move, because it has already have some speed.

All above ASSUMING that you will not put the pedal to the medal (accelerating in Neutral). Shifting to Drive at high RPM is very harmful to the transmission, let alone high RPM may cause problem for the engine as well in the long term.

Kontra Serg.
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