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Old 15th February 2010, 16:18   #1
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Default Hard/Engine Braking in Auto tranny

I have an Hyundai i10 Auto (without ABS) and have some doubts with the braking.

Does the braking method change between MT and AT cars. What is the correct method of applying brakes in Auto transmission cars.

Though the brakes are applied gradually where a stop is anticipated, due to the AT box, the car still keeps moving and at times a last minute hard braking is done to stop the car.

There are times when i feel the car move with the same speed though the brakes are applied (can it be because of the higher RPM's) and a constant hard brake required to slow down the car.

Most importantly, How do i perform an engine brake in AT car, Is it possible.

Mods: I created a new thread because was not able to find one. Please move or merge if any thread already exists.
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Old 15th February 2010, 16:23   #2
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Engine braking is hard to get in AT cars without tiptronic/paddleshift controls. You'll need to brake harder and earlier than MT cars. This is the reason why brake pads and rotors wear out faster in AT cars. Yes, if you let go of the brakes, AT cars will crawl forward without accelerator input.
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Old 15th February 2010, 16:24   #3
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Not sure about the technicalities, but just brake as hard or as little as necessary to bring the car down to the speed you want. No big deal.

If you want more engine braking, you can use the lever to shift down through the gears. Don't know why anyone would want to do that, though
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Old 15th February 2010, 16:27   #4
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Hi ikoneer

There is no special way of braking in ATs as such. Always note that AT cars come with a creep feature. Gradually apply the brakes when coming to a halt. Once the car comes to a halt at say a traffic light, you have to keep your foot on the brake while your car is in D else it will creep forward. If you want to take your foot off the pedal, slot the gear stick into N, wait and then change back to D once you want to move ahead.

There is no proper engine braking in ATs but you can use the 2 and L features to help you while going down a slope etc. One question, do you use both your legs when you drive your car i.e left leg for brakes and right for acceleration? If yes, then that is the wrong way. The left leg is only for resting. Use the right leg for both the purposes.
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Old 15th February 2010, 19:29   #5
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Hi,

For regular braking, a gentle constant pressure should be fine. But once stopped, don't ease off the pressure else vehicle would crawl forward.

In case of emergencies or urgent braking you use use the shift lever to shift to 2. Just shifting it to 2 alone would not produce much result, but with a foot on the brake, it does improve the braking.

The same works even for regular braking, but is not actually needed.

My City is still on its original brake pads.

Last edited by trrk : 15th February 2010 at 19:33.
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Old 15th February 2010, 22:00   #6
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Thanks Immortalz, Tacho, Dippy and trrk for the inputs.

Quote:
Originally Posted by Dippy View Post
One question, do you use both your legs when you drive your car i.e left leg for brakes and right for acceleration?
lol. Nope. Left leg is on the rest pedal and use right leg for the brake and accelerator.

Quote:
Originally Posted by trrk View Post
Hi,
For regular braking, a gentle constant pressure should be fine.

In case of emergencies or urgent braking you use use the shift lever to shift to 2. Just shifting it to 2 alone would not produce much result, but with a foot on the brake, it does improve the braking.
I understand, guess need to get used to it more.

How to accelerate/deaccelerate, should it be a gradual one or a push that moves the rpm higher is required. Which would give better mileage?
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Old 15th February 2010, 22:09   #7
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Ikoneer:

It is only a matter of getting used to the AT. As dippy pointed out the Auto always is engaged so unlike in a manual there is some power to the wheels all the time and you need to push the pedal lower than in an MT when coming to a stop. It doesn't have to be abrupt but generally needs more braking. You'll get used to it soon enough. Nothing wrong with AT and braking. It is just that being your first AT car, it will take some getting used to.

Very often I slot it to N at very long signals to stop having to keep the brake pressed and also save the brakes a little.
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Old 15th February 2010, 23:29   #8
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Post Hand-brake and 'N' at signals

Quote:
Originally Posted by 4x4addict View Post
Ikoneer:
Very often I slot it to N at very long signals to stop having to keep the brake pressed and also save the brakes a little.
I also apply the hand-brake for safety, along with putting it into 'N'.
When I want to move, I first put it into 'D' and then only release the hand-brake.
I feel safer this way, but precious seconds can be wasted, that is once the light turns green it takes that little bit of extra time to bring down the hand-brake. But I feel safer since the car can roll without us knowing if is is in a slope in 'N' w/o the hand-brake or if someone rear-ends you.
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Old 16th February 2010, 00:25   #9
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Quote:
Originally Posted by 4x4addict View Post
Very often I slot it to N at very long signals to stop having to keep the brake pressed and also save the brakes a little.
Your brakes are not used when the car is stationary. There is no relative motion, there is no frictional loss of brake pad material. What you actually save is some wear and tear in the gearbox. If you're in gear, the energy introduced into the gearbox by the engine is absorbed by the AT fluid. Neutral and it's free running.

As for the acceleration, it entirely depends on the transmisison controller and it's programming. You need to get a feel for how the car responds to accelerator inputs. We can't really teach you.
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Old 16th February 2010, 08:32   #10
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a major portion of engine braking is controlled through the ECU also, although not much effective

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Old 16th February 2010, 10:37   #11
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The same method followed by me as well. Shift to N + hand brake at signals.

Quote:
Originally Posted by ImmortalZ View Post
As for the acceleration, it entirely depends on the transmisison controller and it's programming. You need to get a feel for how the car responds to accelerator inputs. We can't really teach you.
what i really want to find out is, in an AT car, what will give better mileage,
a gradual acceleration
or
a press that will move the rpm up and thereby shift to higher gears immediately. Though i find the pick up to drop if i do this
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Old 16th February 2010, 10:50   #12
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Quote:
Originally Posted by ikoneer View Post
what i really want to find out is, in an AT car, what will give better mileage,
a gradual acceleration
or
a press that will move the rpm up and thereby shift to higher gears immediately. Though i find the pick up to drop if i do this
@ikoneer
In any car (irrespective of whether it is MT or AT) gentle acceleration always gives better FE then pressing the padal hard (which is also known as 'driving with heavy foot').
If you are gentle with the accelerator, it upshifts early on and if you press it hard it holds to the gear longer with the system assuming your intent as ' need accelerate quickly'.

Last edited by Guna : 16th February 2010 at 10:52.
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Old 16th February 2010, 11:01   #13
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Quote:
Originally Posted by manim View Post
I also apply the hand-brake for safety, along with putting it into 'N'.
I think putting it into P at signals is better practice.

Read more here :

Need tips on driving and Automatic
(Post #23 if you want to skip straight to my reasoning for putting it in P)


Another thread :
Correct way to drive/use AT


cya
R
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Old 16th February 2010, 19:35   #14
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Quote:
Originally Posted by Rehaan View Post
I think putting it into P at signals is better practice.
This was what I was doing when I first learnt driving the AT.
But now I feel it is overkill to put into 'P' for small stops when the driver is inside the car.

You must put into 'P' when you get down from the car with a running engine (so that the selector-lever does not accidentally gets pushed into 'D').
Also I always apply the hand-brake during regular parking along with 'P', because if I park in a slope, there is stress on the transmission-lock by 'P'.
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Old 16th February 2010, 19:57   #15
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Hi,

You have had answers for your query below. I do hope you have the point here.

Quote:
Originally Posted by ikoneer View Post
How to accelerate/deaccelerate, should it be a gradual one or a push that moves the rpm higher is required. Which would give better mileage?
Yours is a regular automatic and so your acceleration part is different from mine. But gentler acceleration helps you to shift into higher gears faster rather than hard acceleration.

But if you feel that gentle acceleration is not good enough, go for a harder acceleration, but when you have reached a certain RPM, ease off your foot from the accelerator so that the higher gear is chosen. You will eventually learn to modulate the accelerator to give you better acceleration without shifting to a lower gear.

In my case, since my maximum speed is 70kph, I keep my foot on the accelerator so as not to break the egg (imaginary) under it!
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