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Old 2nd March 2017, 00:24   #16
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Re: Automatics : P or N at signals / traffic lights?

Bumping Old Thread but relevant in today's time.

I am reading various posts, few say N on Traffic Signals is not good for the transmission, few says exact opposite.

Can someone explain separately :

1. For Normal Torque Converters (like our i20 (2009) A/T)

2. For CVTs (Baleno, Jazz)

3. For DSGs and DCTs (Polo, Figo)

4. For AMTs/AGTs (Ignis, Alto)

I personally shift to Neutral while waiting on traffic signal (We do have them now here in Goa) as from my instinct I am not comfortable with trying to hold the car with brake pedal pressed for more than say 10 seconds.

Thanks

P.S. : Just found that another thread on Driving Tips for A/T cars, but still request experts to post here on this aspect (of Traffic Signal) ONLY.

Last edited by carwatcher : 2nd March 2017 at 00:33.
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Old 2nd March 2017, 12:15   #17
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Re: Automatics : P or N at signals / traffic lights?

I agree with your way i.e. moving gear lever to N at traffic signals. In my experience driving & talking with AT owners (in west and here in India), it makes all the sense to be in N at traffic signals as the wait would be upwards of few seconds. I mean like in MT, at traffic signals I move the gear to N and pull the hand brake so why any different in ATs.

keeping the car in D mode with foot on the brake pedal will definitely affect life of brake pads and consume more fuel. And is risky too as I found out when I used to live in the west. The car was in D and my foot was on brake pedal as I had just come to halt and was expecting lights to go green. But due to lapse in concentration (for a second or two) I would have slightly taken off the the pressure from brake pedal and rear ended the car in front. There was not even a scratch on that car's rear bumper but the number plate on my car fell off. The occupants of that car called 911, made me wait for few hours and told me to expect a medical law suit or something. It's a usual scam there I think to which some fall prey to. So for sake of saving the brakes, fuel and avoiding risk of bumping into something, being in N seems the best choice.

And some might have developed a habit to move gear lever into P which is worse IMO because one might actually spoil the transmission trying to get lever to P while the car may still be moving.

a snap from an article in topgear "It won't matter if your car has CVT or the conventional multi-speed automatic transmission. Shifting to neutral under most normal conditions is good practice"
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Old 4th March 2017, 08:10   #18
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Re: Automatics : P or N at signals / traffic lights?

Quote:
Originally Posted by carwatcher View Post
Bumping Old Thread but relevant in today's time.

I am reading various posts, few say N on Traffic Signals is not good for the transmission, few says exact opposite.

Can someone explain separately :

1. For AMTs/AGTs (Ignis, Alto)

I personally shift to Neutral while waiting on traffic signal (We do have them now here in Goa) as from my instinct I am not comfortable with trying to hold the car with brake pedal pressed for more than say 10 seconds.

Thanks

P.S. : Just found that another thread on Driving Tips for A/T cars, but still request experts to post here on this aspect (of Traffic Signal) ONLY.
For AMT / AGS, no need to shift to neutral. Simply pull up the handbrake when in D or M mode. It is as good as being in neutral.

You can check this yourself. Even if you release the handbrake, the car won't start moving . It will remain stationary if it is on an even surface.
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Old 4th April 2017, 20:04   #19
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Re: Automatics : P or N at signals / traffic lights?

The more important concern is the wear and tear of the gearbox as the engine continues to run, and the gear is still engaged while in D. So does this mean that one shouldn't stay in D?

Well, I read somewhere that car manufactures are already aware of this issue. Which is why, in most modern automatics, when you break (and come to a complete stand still), it sorts of disengages the clutch. This can be noticed in the lack of movement in the rpm between D and N mode, while the foot is on the break (if the RPM does variate in your car, it's possible that this feature is missing in your car). This means that even though you're in gear, and the engine is running, they're not connected and hence, no wear is taking place.

Of course, there is no harm in shifting to N or P whenever you feel that you're going to be sitting in traffic for a while. It is in fact recommended that you do so, so that in case you accidentally move your foot off the break, the car won't creep forward.

So, if you're worried about staying in D mode causing any damage to your breaks / gearbox - I believe it's not something that you need to worry about.

However, I would strongly recommend you discuss this with the head mechanic at your trusted service station.
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Old 5th April 2017, 16:47   #20
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Re: Automatics : P or N at signals / traffic lights?

^^ I would say that is correct.
I have noticed recently that the RPM is exactly the same in N and (~2-3 secs after) I have pressed the brake in D. I shift to N when the wait time is more than 15-20 secs.

Offtopic, i love the AT on my Creta. It seems to have given me the opportunity to use engine braking while slowing down - something that I never did in my MT cars due to the unpleasant jerk .
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Old 5th April 2017, 16:50   #21
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Re: Automatics : P or N at signals / traffic lights?

N it is! If I go to P I have to cross R and that briefly interrupts my music Shifting from D to N and vice versa is far easier than going all the way upto P and coming to D.

Last edited by Durango Dude : 5th April 2017 at 16:53.
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Old 5th April 2017, 17:03   #22
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Re: Automatics : P or N at signals / traffic lights?

Quick question to CVT users.

When you shift from D to N and vice versa, do you press the lever on the gear while shifting? Can we shift without pressing that lever?

Please share your inputs.
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Old 5th April 2017, 17:05   #23
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Re: Automatics : P or N at signals / traffic lights?

N + Handbrake is the way to go.
Also - kill the engine for longer signals (>30 seconds).

Quote:
Originally Posted by Prodigy07 View Post
Quick question to CVT users.

When you shift from D to N and vice versa, do you press the lever on the gear while shifting? Can we shift without pressing that lever?

Please share your inputs.
Not a CVT user, but guess it's same for CVT / TC gearboxes - it is not required to press the shift button between N<->D.

Last edited by blackasta : 5th April 2017 at 17:06.
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Old 5th April 2017, 17:16   #24
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Re: Automatics : P or N at signals / traffic lights?

Quote:
Originally Posted by Prodigy07 View Post
Quick question to CVT users.

When you shift from D to N and vice versa, do you press the lever on the gear while shifting? Can we shift without pressing that lever?

Please share your inputs.

I think this image I got from the net must answer your queries. these are for Honda CVT transmissions. Thanks for bringing it up as I have also started using a CVT recently and you cleared my doubts as well.
Attached Thumbnails
Automatics : P or N at signals / traffic lights?-cvt-movement.jpg  


Last edited by Durango Dude : 5th April 2017 at 17:18.
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Old 17th April 2017, 19:04   #25
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Re: Automatics : P or N at signals / traffic lights?

Quote:
Originally Posted by Prodigy07 View Post
Quick question to CVT users.

When you shift from D to N and vice versa, do you press the lever on the gear while shifting? Can we shift without pressing that lever?

Please share your inputs.
I recently purchased a Honda BRV , with a CVT automatic transmission. This is my first auto, all previous cars being manuals. The maintenance manual does NOT require pressing button while shifting from N to D and vice versa.
But , both at time of taking delivery , the Sales Executive and later the (Senior) Service Adviser
at time of the first service at 1,000 km, advised me to use the button AT ALL TIMES.
I was a bit confused. My understanding is that the button is required to pressed to prevent inadvertent shifting into R and P.
Both gentlemen gave the analogy that " Just as you would press the clutch in a manual transmission for every shift, it would be better you used the button all the time".
Not sure whether to follow, the book or these guys.
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Old 17th April 2017, 19:19   #26
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Re: Automatics : P or N at signals / traffic lights?

Quote:
Originally Posted by SanjayDalal View Post
I recently purchased a Honda BRV , with a CVT automatic transmission. This is my first auto, all previous cars being manuals. The maintenance manual does NOT require pressing button while shifting from N to D and vice versa. Not sure whether to follow, the book or these guys.
I'd say follow the manual.

The button is to prevent accidental transmission mode changes especially when the car is in motion. I depress the button each time, but that's just me.

When driving an automatic car, at traffic signals or temporary halts >1 minute I stick the transmission into N and use the parking brake to prevent any roll forward/backward. I use the main brakes for momentary stops for e.g. at a toll booth.
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Old 17th April 2017, 19:21   #27
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Re: Automatics : P or N at signals / traffic lights?

Quote:
Originally Posted by SanjayDalal View Post
I recently purchased a Honda BRV , with a CVT automatic transmission. This is my first auto, all previous cars being manuals. The maintenance manual does NOT require pressing button while shifting from N to D and vice versa.
But , both at time of taking delivery , the Sales Executive and later the (Senior) Service Adviser
at time of the first service at 1,000 km, advised me to use the button AT ALL TIMES.
I was a bit confused. My understanding is that the button is required to pressed to prevent inadvertent shifting into R and P.
Both gentlemen gave the analogy that " Just as you would press the clutch in a manual transmission for every shift, it would be better you used the button all the time".
Not sure whether to follow, the book or these guys.
The book - follow the book.

P<->N shifting without pressing the button actually prevents inadvertent shift to R while the car is in motion, which can be catastrophic for a gearbox.
If you are shifting between P<->N by pressing the button, you are actually increasing the chances of the aforementioned to happen.
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Old 17th April 2017, 19:26   #28
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Re: Automatics : P or N at signals / traffic lights?

Quote:
Originally Posted by Diesel lover View Post
For AMT / AGS, no need to shift to neutral. Simply pull up the handbrake when in D or M mode. It is as good as being in neutral.

You can check this yourself. Even if you release the handbrake, the car won't start moving . It will remain stationary if it is on an even surface.
AFAIK, when you engage D or M and keep your foot off pedals, the car will creep forward unless it is on a steep incline.** To stop this from happening, you need to apply brake or handbrake. That is, the car will try to creep forward and you'll keep her arrested by using brakes till a green signal. This tug-of-war is not advisable because the powertrain is continuously trying to do its job and the clutch may be "burning".

The proper practice is you put the car into N and apply handbrake or main brake. This procedure will put nil load on clutch and less load on brake pads, as the engine, while powering the AC and alternator, is not providing power to the transaxle. Shift into D and drive away when you get the signal.

** (If your car has hill hold control, it will hold for a couple seconds before rolling back.)

Correct me if I am wrong, please.

Last edited by sandeepmdas : 17th April 2017 at 19:31.
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Old 17th April 2017, 23:12   #29
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Re: Automatics : P or N at signals / traffic lights?

R2D2 and Blackasta, I am inclined to agree with you. I have come to the same conclusion. Incidently, moving the gear lever from D to S REQURIES you to push the button on the gear lever. The Honda BRV has paddle shifters which one can use in S mode. But sifting from S to D does NOT require pushing the button. Till date I have covered just 1800km. Will prefer to cover at least another 1000-2000km before shifting to S and using paddle shifters.
Sandeepmdas: You are absolutely right, with regards to your post regarding car creeping forward. I have spent many hours doing research on the Internet.
The conclusion I have also arrived at is ; if foot brake is applied fully at a signal, there should not be a problem if the car with auto transmission (CVT or conventional) is equiped with a torque converter. The transmission fluid will , take care of the the 'stress' on the gears. But one should NOT allow the car to creep forward for a longer period of time. This is particularly true for a CVT. When the lights turn green, lift off on the footbrake, and gently press the accelerator. These actions should minimise wear and tear of the automatic transmission.
Just a note, I am using my BRV only for longer distances, Mumbai to Pune/Lonavala , etc. Ironically, I use a manual transmission, Hyundai Eon for local driving, since it is easy to maneuver and park in confined spaces in Mumbai.
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Old 17th April 2017, 23:41   #30
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Re: Automatics : P or N at signals / traffic lights?

R2D2 and Blackasta, Thank you both, for your input which validates my thinking.
Sandeepmdas, one point, which applies to CVTs ( not sure whether it applies to conventional autos), based on the articles I read while surfing the net, CVTs do not take kindly to 'creep'. Ideally, one should release the foot brake and at once accelerate gently. Not sure of the technology part of it, but I do follow this practice as far as possible.
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