Shifting to N while the engine is running

Hyaenidae · October 9, 2019

Ok so I'm going to sound like a total noob for asking this question but...

Have you guys ever heard of an automatic transmission (conventional automatic, not CVT or DCT) wearing off when it's in Neutral while idling the engine and the vehicle is stationary?

I came across this post in an automotive forum that said shifting to N while stopped at stoplights/traffic could induce more wear and tear to the transmission clutches (not linkages and other stuff that gets used when using the shifter but the clutch plates themselves) than leaving it in gear and using the brake to keep the vehicle stationary. (I'll try and link the post, I was reading it on my mobile)

I myself was in the opinion that the wear caused by either method is similar and negligible, but I just wanted to ask: have you guys ever heard of such a phenomenon?

Edited October 9, 2019 by Hyaenidae

trinity · October 10, 2019

I too had your question when I bought the car as I was driving a manual before. When driving a manual in city traffic, what I’m used to do at a red light is keep the gear in 1st position , press the clutch and engage the parking brake. I was easy as I just had to release the parking brake and the clutch to fly out of the light when it’s green.

I don’t know why but holding the car with the brake while the gear position is in D in an auto car feels very uncomfortable to me. So when I bought the EX I too asked this question from @Davy. His suggestion was also not to shift from D to N regularly as it could cause a slight wear of the clutch.

I read the parts in the manual where it says not to keep it on D while stationary for a longer period of time and it’s ok to keep in D for a shorter period of time like at a traffic signal.

So, in a traffic light where it stays over 30 seconds I’m shifting to N, in other instances I’m keeping on D while engaging the brake.

Here im attaching the two parts of the owners manual which I referred above for easy reference.

Hyaenidae · October 9, 2019

Found the post I was referring to:

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When the car is in D and you start the engine the hydraulic pump in the automatic transmission is not providing fluid pressure until the engine starts.

This fluid pressure is used to engage clutches in the transmission to engage first gear or reverse.

An automatic transmission does not have gears like a manual transmission which are physically meshed into one another or engaged.

The gears in an automatic transmission are always engaged or locked in but they are coupled to the drive shaft by multiple different clutches that are selected either by you or automatically. This is called the planetary gear and clutch system and it is very difficult to conceptualize.

In an automatic transmissions N is actually the same as P in that none of the clutches are engaged except in P there is a mechanical connection to an internal transmission brake. This brake has nothing to do with your wheel brakes and it come on mechanically so the engine does not need to be running for it to work. But you should not rely on it alone when parking on steep hills.

In D when you’re at a stop the main forward clutches are engaged and the torque converter is providing pressure to rotate the forward gear but it does not rub or wear when it is doing this. Because of this resistance to free rotation in the transmission the engine begins to slow. In a modern car there is an idle control valve which the computer opens to increase air entering the engine so the engine does not stall. So there is actually more air entering and the computer senses this and adds a bit more fuel as well. So in D at the light your car will use a little more fuel than if it was in N.

Also the wheel brakes are not rubbing but are stopped and they will not wear at all while holding the forward creep of the car when in D.

The forward creep is caused by the transmissions torque converter. There is nothing slipping or wearing or heating up to any significant extent in there. It’s all done hydraulically and nothing is wearing to worry about. BUT!!!! When you are in N and the engine is turning and the wheels are stopped then for this to occur the main forward clutch is disengaged and it is SLIGHTLY SLIPPING. So the clutch plates are wearing.

So you are actually wearing out the main wear component in an automatic transmission being the clutch plates if you shift from D to N at a stop. The only advantage is your saving a very small amount on fuel.

Personally I DO NOT and I have been told by an automatic transmission engineer that you should never shift the transmission from D to N at the lights. The reason being you are wearing your clutch plates in your transmissions. It also gets hotter because of the friction and the dirtier transmission oil then contributes to other component failures.

Also it’s dangerous to be sitting there in N. You may need to drive away all of a sudden to avoid an accident but in N there is less chance of do this. You also may select the wrong setting like R when you wanted D.

If N should be selected at the lights then engineers would have incorporated this into the design. But they did not. On some fuel saving cars the engine now shuts off at the lights so obviously N is selected automatically by the computer during the shutdown period so the car can be restarted. But the engine is not turning so the clutch plates are not slipping and wearing in this type of fuel efficient car.

Also if your car vibrates in D at the lights then you need to get it serviced. It should not vibrate excessively at the lights if everything is working fine.

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Link:

https://mechanics.stackexchange.com/a/18561

alds · October 9, 2019

On 10/9/2019 at 12:33 PM, Hyaenidae said:

main forward clutch is disengaged and it is SLIGHTLY SLIPPING

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I think this is a design feature. They are multiplate wet clutches. So they can tolerate slight slippage by design. As for the heat generation, I don't think wet clutches generate considerably higher heat than the torque converter itself.

K.o.N.o.S · October 9, 2019

On 10/9/2019 at 11:46 AM, Hyaenidae said:

Have you guys ever heard of an automatic transmission (conventional automatic, not CVT or DCT) wearing off when it's in Neutral while idling the engine and the vehicle is stationary?

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Let's assume the waiting time is more than 1 min. I think in such instances it's better to use "P" + handbrake as opposed to "N". "Neutral" is there for specific situations like towing the car or in case if you need to push the car right? It has not been designed to use at traffic lights..?.

Hyaenidae · October 9, 2019

On 10/9/2019 at 2:41 PM, alds said:

I think this is a design feature. They are multiplate wet clutches. So they can tolerate slight slippage by design. As for the heat generation, I don't think wet clutches generate considerably higher heat than the torque converter itself.

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So is this true? Does idling while the transmission is in Neutral cause excessive wear?

Hyaenidae · October 9, 2019

On 10/9/2019 at 5:09 PM, K.o.N.o.S said:

Let's assume the waiting time is more than 1 min. I think in such instances it's better to use "P" + handbrake as opposed to "N". "Neutral" is there for specific situations like towing the car or in case if you need to push the car right? It has not been designed to use at traffic lights..?.

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But our owners manual says:

"For short waiting periods, such as at traffic lights, the vehicle can be left in gear and held stationary with the service brake.

For longer waiting periods with the engine running, the selector lever should be placed in the “N” (NEUTRAL) position."

Davy · October 10, 2019

On 10/10/2019 at 1:01 AM, trinity said:

So, in a traffic light where it stays over 30 seconds I’m shifting to N, in other instances I’m keeping on D while engaging the brake.

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Yes, this makes sense and aligns well with what's mentioned in the manual. I've seen some of my friends shift to Neutral every other time the vehicle comes to a halt in a traffic jam which is quite excessive and this is what needs to be avoided.

On 10/9/2019 at 5:09 PM, K.o.N.o.S said:

Let's assume the waiting time is more than 1 min. I think in such instances it's better to use "P" + handbrake as opposed to "N". "Neutral" is there for specific situations like towing the car or in case if you need to push the car right? It has not been designed to use at traffic lights..?.

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When you shift from D to P, you have to go through several positions D > N > R > P, which is not that great IMO. The Neutral position is right next to D, so it makes more sense to just move the shifter one notch between D and N.

K.o.N.o.S · October 10, 2019

I have only used "N" position when parking the Car. Get the vehicle to a complete stop. apply the Hand brake, Put the gear to "N" while applying the service brake. then shift the Gear to "P", foot off the service brake and then stop the engine.

Hyaenidae · October 10, 2019

On 10/10/2019 at 3:28 AM, K.o.N.o.S said:

I have only used "N" position when parking the Car. Get the vehicle to a complete stop. apply the Hand brake, Put the gear to "N" while applying the service brake. then shift the Gear to "P", foot off the service brake and then stop the engine.

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For me it's

1. Get the vehicle to a complete stop.

2. Put the gear to "N" while applying the service brake

3. Apply the Hand brake.

4. Foot off the service brake

5. Apply the service brake again

6. Shift the Gear to "P", foot off the service brake and then stop the engine.

K.o.N.o.S · October 10, 2019

On 10/10/2019 at 3:32 AM, Hyaenidae said:

For me it's

1. Get the vehicle to a complete stop.

2. Put the gear to "N" while applying the service brake

3. Apply the Hand brake.

4. Foot off the service brake

5. Apply the service brake again

6. Shift the Gear to "P", foot off the service brake and then stop the engine.

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Spot on!! I missed point 5.?

BlueRaiden · October 11, 2019

When i bought my car also i researched on this. Im not an expert, but my understanding is changing gears often and leaving the car in D while stationary both introduce wear and tear to the system.

I have no way to know if my car manual specifies anything because it is in Japanese (Allion 2008).

My method is as same as @trinity if the wait is less than 60 seconds leave it in D, if it is more put it in N, engage parking brakes and release service brakes. Over 3 mins stop the engine altogether.

It is a good thing that you @Hyaenidae discussed this. I want to know about it as well.

trinity · October 11, 2019

On 10/10/2019 at 3:32 AM, Hyaenidae said:

For me it's

1. Get the vehicle to a complete stop.

2. Put the gear to "N" while applying the service brake

3. Apply the Hand brake.

4. Foot off the service brake

5. Apply the service brake again

6. Shift the Gear to "P", foot off the service brake and then stop the engine.

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Is there any particular reason for following 2,3,4&5?

With me its,

1.Stop (Keeping the foot on the service brake)

2.Shift to "P"

3.Engage parking brake.

4.Release the the service brake.

Edited October 11, 2019 by trinity

iRage · October 11, 2019

On 10/11/2019 at 11:02 AM, trinity said:

Is there any particular reason for following 2,3,4&5?

With me its,

1.Stop (Keeping the foot on the service brake)

2.Shift to "P"

3.Engage parking brake.

4.Release the the service brake.

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A lot of people do the 2,3,4&5 routine with the intent of not putting strain on the gear box. After putting it in neutral and applying the P brake and taking the foot of the service brake...any strain of vehicle roll gets put on the brakes instead of the gearbox....

trinity · October 11, 2019

On 10/11/2019 at 11:41 AM, iRage said:

A lot of people do the 2,3,4&5 routine with the intent of not putting strain on the gear box. After putting it in neutral and applying the P brake and taking the foot of the service brake...any strain of vehicle roll gets put on the brakes instead of the gearbox....

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So my way would put strain on the GB??

iRage · October 11, 2019

On 10/11/2019 at 12:15 PM, trinity said:

So my way would put strain on the GB??

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To be honest...I don't know...what I have noticed is in the Fortuner if I just put it on P and just let go of everything, when I start the next day and try putting it in to D there is a bit of a thud....so I started doing it on this Fortuner after noticing it in my wife's Vitz (2003 1.3L)......I can't remember anything like that in the the RAVs or Hilux Surf....

Hyaenidae · October 11, 2019

On 10/11/2019 at 11:02 AM, trinity said:

Is there any particular reason for following 2,3,4&5?

With me its,

1.Stop (Keeping the foot on the service brake)

2.Shift to "P"

3.Engage parking brake.

4.Release the the service brake.

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@trinity You see, when you put the gear into P, you engage the parking pawl.

https://en.wikipedia.org/wiki/Parking_pawl

When you engage the parking pawl before applying the parking brake, the car is being held by the parking pawl instead of the parking brake.

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Most vehicle manufacturers and auto mechanics do not recommend using the transmission's parking pawl as the sole means of securing a parked vehicle, instead recommending it should only be engaged after first applying the vehicle's parking brake. Constant use of only the parking pawl, especially when parking on a steep incline, means that driveline components, and transmission internals, are kept constantly under stress, and can cause wear and eventual failure of the parking pawl or transmission linkage. The pawl might also fail or break if the vehicle is pushed with sufficient force, if the parking brake is not firmly engaged. Replacement can be an expensive operation since it not only requires removing the transmission from the vehicle, but it's usually the first component to be installed in the gearbox case during a complete rebuild.

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So, when I shift the car to N and apply the parking brake, (Steps 2 and 3) the car is being held by the parking brake instead of the parking pawl. Steps 4 and 5 are to ensure that the parking brake is firmly engaged.

My previous car, a Belta, used to make an audible "thud" every time I shifted from P to D, just like @iRage said - When I tried this method for the first time there was no sound at all! I've been parking every auto car this way ever since.

Edited October 11, 2019 by Hyaenidae

Twin Turbo · October 11, 2019

While driving, kweep the ggear selector in D when you park the car after the drive stop the engine after shifting to P

I f you want to avoid wear on the gearbox, don't use it.

Stick to recommended maintenance by the manufacturer.

If you intend to park the vehicle for more than 5 mins, select P.

Magnum · October 11, 2019

If I’m gonna sit for like a minute at a traffic light I shift to N and apply the parking brake. I don’t think Shifting between gears often will damage the gearbox but it will wear out a small washer behind the gear selector. I have seen that happen once on a van but then again that was a rented van and it had a gearbox issue, D was stuck in 3rd so you had to shift between 2 and L. Doing that often probably wore out the washer.

It’s not good engage park before engaging the parking. The loud thud you get when shifting back to D is the sound from the gearbox. When you shift into Park before applying parking brake, the gearbox holds the vehicle in place rather than the parking brake.

Davy · October 13, 2019

On 10/11/2019 at 12:15 PM, trinity said:

So my way would put strain on the GB??

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Depends on what sort of incline the car is parked on. If it's perfectly level ground, it's not going to put any strain on the gearbox because the car will not try to move anywhere. This is not the case in reality because even the slightest dip or imperfection on the ground would cause the car to want to "settle in". So a slight amount it strain can be on the gearbox even on level ground. On an incline, this become significantly more as the gearbox is holding the car from moving. If the parking brake is weak, this becomes even worse.

So as a practice, it's good to follow the steps suggested. Before you know it, this will become a routine that you will do involuntarily within a couple of seconds.

iRage · October 13, 2019

On 10/13/2019 at 1:27 AM, Davy said:

So as a practice, it's good to follow the steps suggested. Before you know it, this will become a routine that you will do involuntarily within a couple of seconds.

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True....looking back...it is something I do even with a manual transmission...so I never actually thought about what I was going even in the Auto...and with the Vitz if I remember right it was my wife who asked why it was doing that....

trinity · October 14, 2019

On 10/13/2019 at 1:27 AM, Davy said:

Depends on what sort of incline the car is parked on. If it's perfectly level ground, it's not going to put any strain on the gearbox because the car will not try to move anywhere. This is not the case in reality because even the slightest dip or imperfection on the ground would cause the car to want to "settle in". So a slight amount it strain can be on the gearbox even on level ground. On an incline, this become significantly more as the gearbox is holding the car from moving. If the parking brake is weak, this becomes even worse.

So as a practice, it's good to follow the steps suggested. Before you know it, this will become a routine that you will do involuntarily within a couple of seconds.

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Pardon me for my ignorance, could you please clarify this,

As I explained earlier what I would do is that Stop the car, while keeping my foot on the service brake, shift to 'P' position, engage the parking brake and release the service brake. Doing so, what I feel is that braking would shift from service to parking without causing any burden to the gear box.

Whats the difference of 1 vs 2 in the below steps,

1.SB >> Shit to 'N' >> Release SB >> Engage PB >>Engage SB>>Shift to 'P' >> Release SB

&

2.SB >> Shit to 'P'>> Engage PB>> Release SB

If No 01 is the ideal way, what should be done when stopping the car after reversing? Because 'R' is between 'N' and 'P'

Shift to 'N' and Engage PB thereafter shift to 'P'????

Hyaenidae · October 14, 2019

On 10/14/2019 at 10:01 AM, trinity said:

Pardon me for my ignorance, could you please clarify this,

As I explained earlier what I would do is that Stop the car, while keeping my foot on the service brake, shift to 'P' position, engage the parking brake and release the service brake. Doing so, what I feel is that braking would shift from service to parking without causing any burden to the gear box.

Whats the difference of 1 vs 2 in the below steps,

1.SB >> Shit to 'N' >> Release SB >> Engage PB >>Engage SB>>Shift to 'P' >> Release SB

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This should be corrected as

SB >> Shift to N >> Engage PB >> Release SB >> Engage SB >> Shift to P >> Release SB

Releasing the SB while the gear is in N without engaging the PB would make the car roll neh, that would be quite dangerous on an incline. You should release the SB only after the PB is engaged, to make sure that the PB is firmly applied and it is holding the car completely still. After you made sure that the PB is holding the car, you can engage the SB again and shift the car to P.

When I was using the 2nd method my Belta used to make the thud sound, that went away when using the 1st method. Haven't tried the 2nd method on the EX yet, been using the 1st method since it was brand new.

When reversing,

Reverse to place>> Engage SB>> Shift from R to N >> Engage PB >> Release SB >> Engage SB >> Shift to P >> Release SB

Edited October 14, 2019 by Hyaenidae

Davy · October 14, 2019

On 10/14/2019 at 10:01 AM, trinity said:

Pardon me for my ignorance, could you please clarify this,

As I explained earlier what I would do is that Stop the car, while keeping my foot on the service brake, shift to 'P' position, engage the parking brake and release the service brake. Doing so, what I feel is that braking would shift from service to parking without causing any burden to the gear box.

Whats the difference of 1 vs 2 in the below steps,

1.SB >> Shit to 'N' >> Release SB >> Engage PB >>Engage SB>>Shift to 'P' >> Release SB

&

2.SB >> Shit to 'P'>> Engage PB>> Release SB

If No 01 is the ideal way, what should be done when stopping the car after reversing? Because 'R' is between 'N' and 'P'

Shift to 'N' and Engage PB thereafter shift to 'P'????

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The parking brake is applied only on the rear wheels. On a front wheel drive car like your EX, shifting to N and releasing the service brake (while parking brake is engaged) takes the tension off the front wheels before shifting into P and allows them to "settle". This helps prevent strain on the transmission to a degree.

It must be said that the gearbox will not be wrecked or anything if you don't follow this. On my RalliArt for example, it makes no sense to do this as the car is an AWD, and the P position is activated electronically through hydraulic actuators within about half a second of shifting to P.

But on the Mazda 323 (front wheel drive), there's a thud when I shift out of park the next time I start the car - if I forget to do this (or if my wife is the one who stopped the car ?). Especially when parked on a slope.

Edited October 14, 2019 by Davy

trinity · October 14, 2019

On 10/14/2019 at 10:34 AM, Hyaenidae said:

This should be corrected as

SB >> Shift to N >> Engage PB >> Release SB >> Engage SB >> Shift to P >> Release SB

Releasing the SB while the gear is in N without engaging the PB would make the car roll neh, that would be quite dangerous on an incline. You should release the SB only after the PB is engaged, to make sure that the PB is firmly applied and it is holding the car completely still. After you made sure that the PB is holding the car, you can engage the SB again and shift the car to P.

When I was using the 2nd method my Belta used to make the thud sound, that went away when using the 1st method. Haven't tried the 2nd method on the EX yet, been using the 1st method since it was brand new.

When reversing,

Reverse to place>> Engage SB>> Shift from R to N >> Engage PB >> Release SB >> Engage SB >> Shift to P >> Release SB

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On 10/14/2019 at 11:29 AM, Davy said:

The parking brake is applied only on the rear wheels. On a front wheel drive car like your EX, shifting to N and releasing the service brake (while parking brake is engaged) takes the tension off the front wheels before shifting into P and allows them to "settle". This helps prevent strain on the transmission to a degree.

It must be said that the gearbox will not be wrecked or anything if you don't follow this. On my RalliArt for example, it makes no sense to do this as the car is an AWD, and the P position is activated electronically through hydraulic actuators within about half a second of shifting to P.

But on the Mazda 323 (front wheel drive), there's a thud when I shift out of park the next time I start the car - if I forget to do this (or if my wife is the one who stopped the car ?). Especially when parked on a slope.

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Got it. Thanks guys. Will keep this in mind.

Dee Jay · October 14, 2019

On 10/10/2019 at 3:32 AM, Hyaenidae said:

For me it's

1. Get the vehicle to a complete stop.

2. Put the gear to "N" while applying the service brake

3. Apply the Hand brake.

4. Foot off the service brake

5. Apply the service brake again

6. Shift the Gear to "P", foot off the service brake and then stop the engine.

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