Do I need to switch N position when waiting for Traffic Light?

[hans_fh]

I just wonder if switching the transmission position to N when waiting for the traffic light can use less fuel than I press Brake Pedal and hold on D position

THX

[YamilR]

I just wonder if switching the transmission position to N when waiting for the traffic light can use less fuel than I press Brake Pedal and hold on D position

THX

Nope, thats just a waste of time, at the contrary you'll probably forget to change it when green and just going to over rev the engine:thumbdown:

[swng]

A moot point. IMHO, whatever you choose to do, the effect on the fuel economy will be minimal.
If the wait is short, I prefer to stay in the 'D' position. In case of emergency, I can just step on the gas and go without delay.
In the case of a long delay, say for example, when an accident holds up the traffic and it is known that I will have to stop for quite a while, I will shift to the 'P' position so that my foot does not have to step on the brake for too long (note: on a steep slop, any long stop will call for the use of the hand brake in addition to anything else). Fatigue and loss of concentration can cause mishaps.

[Yaris Dick]

No.

[Chris07LB]

Nope, thats just a waste of time, at the contrary you'll probably forget to change it when green and just going to over rev the engine:thumbdown:


+1 :thumbdown:

[eco]

It could even wear out the transmission faster,I never put it in neutral.

[johnnyfive]

motor will also rev higher when in neutral ;) not saying it really uses more gas to do so, but thats what it does :)

[ECHOKnight2000]

I always put my car in neutral (I have an auto), I thought it was better for that. I only put it in if I know I will be waiting for awhile...but I usually have my hand on the shifter in case I have to put it in drive fast but I make sure I don't step on the gas too early while shifting and what not cause I know that's hard on an automactic.:iono: :rolleyes:

[07WYarisRS]

It does not hurt the trans to shift to neutral while waiting for extended amounts of time. But it's not needed for short stop light stops. Just keep it in drive unless your going to be sitting for a while.

I shift to neutral while sitting at the CAN/US border crossings for 20-40 minutes because it's easier on the transmission.

Think about it, when you take your foot off the brake it will move ahead without touching the accelerator, thats because there is drag between the clutches in the transmission. Holding it there in drive for extended amounts of time causes the clutches to slip constantly creating heat and wear on the clutches and breaks down the oil quickly.
When you shift to neutral it allows the main and secondary shafts to spin freely at matched speeds with no load so you eliminate the slipping.

But no you don't need to and no it's won't really make a difference on the fuel economy shifting at short stops.

[eTiMaGo]

07WYarisRS, I thought the torque converter ("clutch") on an automatic transmission used the drag of a viscous fluid to cause the transmission side of the device to spin? Thus on D at low revs, all you are doing is spinning this fluid around, which would put some resistance on the engine, but it sould not wear anything out?

Or am I wrong and the Yaris auto transmission is using a clutch system like a manual one?

[07WYarisRS]

BOTH

Automatics transmissions do not use a primary engagement/disengagement clutch like a manual trans does but they do use clutches.

With a manual trans you have a single clutch on the flywheel and inside the manual transmission is sets of gears, input and output shafts with syncros to switch gears

With an automatic you have a torque convertor on the flywheel is basically a centrifugal hydraulic pump witch acts like an automatic clutch as well as a high pressure pump to puch fluid to the clutches. But inside an automatic transmission is several sets of clutches and electronic valve body and bands that control the input to the main Planitary gearset. An automatic trans uses the pressurized fluid through the valve body to engage and disengage the clutches for each gear. When idling the pressure is low and it applies less pressure to the clutches to keep the car from moving. As you step on the gas the pressure builds up more and forces the clutches to engauge.
When you shift to neutral the valve body closes the piston that and redirects the fluid removeing pressure from the clutch.
All that being said the car is designed to sit at a stop in gear not moving.
but like I said shifting to neutral will not hurt and can add a bit of life to the clutches and fluid over time.
I usually don't recommend it because so many people don't take the time to shift slowly.
Just like when people are backing up and slip it into drive while still rolling backwards. That tears up the clutches. When shifting from park to drive or neutral to drive the shift must be complete with a second or two pause before stompin' on the gas. This allows the fluid do it's job and eliminate clutch damage.


check this out for more MUCH more detailed pics and information
http://auto.howstuffworks.com/automatic-transmission.htm

and a pic of a Yaris transmission apart. at the back of the bench(middle) is the clutch packs
http://img.photobucket.com/albums/v104/Toytech/Yaristrans2.jpg

[BMGYaris]

All that being said the car is designed to sit at a stop in gear not moving.




HUM, what do you mean it is designed to sit at a stop and not move? even if im on an uphill incline not moving if i let go of the break it will slowly start popping and driving forward up the hill. Def. cant let go of the break when im flat on the ground! so what do you mean by sit at a stop in gear not moving? in D and not move forward?:confused:

[07WYarisRS]

I meant you don't have to shift to neutral or park when you stop at a light ot intersection or what ever.
keep your foot on the brake and the transmission in drive. The transmission was desinged to be kept in drive with no need to shift out of drive to neutral when stopping briefly.

You can...it won't hurt it, but doing so is not necessary.

There is normal wear that will be accelerated buy constantly shifting at stop lights that you may otherwise never incounter.

[ECHOKnight2000]

I usually don't recommend it because so many people don't take the time to shift slowly.
Just like when people are backing up and slip it into drive while still rolling backwards. That tears up the clutches. When shifting from park to drive or neutral to drive the shift must be complete with a second or two pause before stompin' on the gas. This allows the fluid do it's job and eliminate clutch damage.



When I back out of my driveway or other places (sometimes) I obviously put it in reverse then when I get going shift into neutral till I really slow down then shift into drive when I have to go, is that alright? I make sure I stop the car enough to shift into drive and not do what you mentioned and put it in drive when the car is still going backwards, sometimes I accidently do it and obviously the car jerks and I know this isn't good for the tranny. Or sometimes I have it in neutral at a stop light and I'm going up hill, I have my foot on the break obviously but let go of the break and shift into drive before the car rolls backwards so it doesn't f-up the tranny but sometimes the car jerks cause I let it go too far before putting it in drive.

[07WYarisRS]

When backing up come to a complete stop, then shift to drive. i don't even recommend shifting to neutral while rolling back wards.
When you do shift to drive make sure the car is at a complete stop then when you feel the car put load onto the engine and then you know it's safe to go. This takes a second or less but doing so the transmission will last the lifetime of the car.
Jumpin back and forth even with the car rolling a little bit or jumpin' the gun kills the transmissions and is why so many people think auto trans are not relaible. They are used improperly and abused.

[Lowfront]

So I've heard many people here with the 5-speed talk about how they put it in neutral all the time to save on gas.. For example, going down hill, or long before a stop sign so you slow down like that. Is this bad for the car?

[the_saint]

So I've heard many people here with the 5-speed talk about how they put it in neutral all the time to save on gas.. For example, going down hill, or long before a stop sign so you slow down like that. Is this bad for the car?
With a stick? No.

[eTiMaGo]

not bad for the car, BUT, you only have the brakes to reply on, no engine braking, so down a long hill this may cause the brakes to fade, or in an emergency, it's always good to also ahve the engine brake to rely on.

Still, that feeling of just floating down hill silently is hard to beat!

[07WYarisRS]

So I've heard many people here with the 5-speed talk about how they put it in neutral all the time to save on gas.. For example, going down hill, or long before a stop sign so you slow down like that. Is this bad for the car?

With a manual or standard it is hard on them
Shifting into gear or engaging the clutch at unmatched speeds is hard on the trans and shortens the life of the clutches on both automatic and and manual transmission.
Not to mention a free wheeling car is very unsafe.
engauging the clutch on an engine that is at idle speed while the car is moving just burns up the clutches.
Using just the brakes to slow a car, boils the fluid and wears out the pads, rotors and wheel bearings very quickly.

Just keeps your cars in drive/gear the way they were meant to be driven.
you not going to notice much difference in MPG and it makes for a lot safer driving keeping the car in gear.

This makes the difference between a clutch that lasts a couple years or 15 years.
or brakes that last 50,00km or 150,000km
Clutches and brakes are not covered by warranty and are costly to repair...

It's like a "hard on" if you want to keep it for a long time don't phuck with it LOL

Same goes for the clutch and brakes. If you want to keep repair costs down drive it normal.

[eco]

LOL,well said.

[Katana]

not bad for the car, BUT, you only have the brakes to reply on, no engine braking, so down a long hill this may cause the brakes to fade, or in an emergency, it's always good to also ahve the engine brake to rely on.

Still, that feeling of just floating down hill silently is hard to beat!


+1.

I also have to say, that from what I have read, the car saves more fuel if, on a downhill road, we select a high gear(5th-4th) than selecting neutral because we help the engine to understand that we don't need to spend gas.