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Old 1st May 2014, 23:19   #16
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Default Re: Brakes - A few tips that could help

One point to add ref. Handbrakes.
When leaving the car unused for a long period of time. Don't engage the hand-brake. If you do, prolonged contact between the rotors and the pads, will cause them to fuse together.
Then when you are back , and disengage the hand-brake, the wheel will be locked.
Always use wheel chocks and/or put the car into gear when parking for a long time.
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Old 2nd May 2014, 09:44   #17
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Default Re: Brakes - A few tips that could help

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Originally Posted by VeyronSuperSprt View Post
Rotors that show blue spots or have a darker colour in some areas cannot recover and should be replaced along with the brake pads.

Some people advise skimming the rotors as a cost saving measure to remove the DTV( Disc thickness variation / warping of rotors), but this needs to be done after a proper inspection as skimming of rotors have been known to make the rotors thinner than the minimum safety level and has resulted in the rotors cracking under stress.

It is best that replacement of rotors / pads are done at the earliest if found required to prevent damage to suspension / steering components.
Hi VSS, a well-written article. A quick query:

Some manufacturers / service centres advise changing the pads and discs as a set, while others simply change the pads and don't change or skim the discs.

Provided there is no judder, what do you advise? When do you suggest to change just the pads, and when should the discs be changed? What are the indicators / rules of thumb for changing a disc?
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Old 2nd May 2014, 09:55   #18
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Default Re: Brakes - A few tips that could help

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Originally Posted by SS-Traveller View Post
Hi VSS, a well-written article. A quick query:

Some manufacturers / service centres advise changing the pads and discs as a set, while others simply change the pads and don't change or skim the discs.

Provided there is no judder, what do you advise? When do you suggest to change just the pads, and when should the discs be changed? What are the indicators / rules of thumb for changing a disc?
Whenever the Discs are changed the pads also have to be changed. This is because the old pads would have got set with the grooves in the old disc and will not match the new smooth disc

If there is no judder, only pads can be changed.

The discs need to be changed if you have judder or if the thickness of the disc has worn below the min threshold value. This is measured using a vernier caliper in the service center. Otherwise there is no reason why one should change the disc
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Old 2nd May 2014, 10:47   #19
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Default Re: Brakes - A few tips that could help

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Originally Posted by SS-Traveller View Post
Hi VSS, a well-written article. A quick query:

Some manufacturers / service centres advise changing the pads and discs as a set, while others simply change the pads and don't change or skim the discs.

Provided there is no judder, what do you advise? When do you suggest to change just the pads, and when should the discs be changed? What are the indicators / rules of thumb for changing a disc?
Hi SST, Thanks for the appreciation

If there is no judder there is no need to change the discs provided they have not reached their service limit. The service limit is prescribed by the manufacturer and will be available with the ASS. As a rule of thumb, the discs would need to be changed at every third replacement of the brake pads.

However the rule of thumb is applicable if there is no other external damage to the discs such as grooving on the discs by a stone stuck between the pads and discs / salt based corrosion of the discs / avoiding use of high performance pads etc and also by not subjecting them to excessive wear and tear such as driving on the brakes etc.

The pads are also to be changed when they near their wear limits there is an indicator of this on some pads (in some cases there is a groove on the pad which when worn out indicates the wear limit). The wear limits prescribed by the manufacturer will also be available with the ASS.
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Old 2nd May 2014, 13:01   #20
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Default Re: Brakes - A few tips that could help

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Originally Posted by Rachit.K.Dogra View Post
So if you are driving on downhill hilly road, what will make the brake pads wear more if you start slowing earlier for the turn and apply lighter pressure on brakes or brake slightly later with more pressure on the brakes?
Buddy,

On a downhill road, don't change your braking style based on brake pad wear. Instead, do so based on safety, traffic conditions and as the situation may demand. Brake pads are cheap, damage to you / your car won't be

Also, remember to use engine braking when going downhill.

Related Thread (ARTICLE: Safe Driving on Indian Highways & Ghats)
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Old 3rd May 2014, 07:49   #21
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Default Re: Brakes - A few tips that could help

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Actually there is no vibration in my car at any speed from 70-170+ its absolutely smooth, plus if i leave the steering wheel the car goes straight as an arrow. No left or right pull. Plus there is no uneven wear and tear in any tyres.
As you say the car is absolutely smooth at all speeds, there is no point in doing the balancing with the chances of spoiling a good setting.

In order to reduce the judder it would be advisable to try aggressive braking a few times as suggested earlier. Aggressive braking will reduce the intensity of any judder. If it is minor, it could remove the judder completely too. If your judder still exists after the aggressive braking exercise, then the only remedy will be to have the discs changed. (Note: Do not do the aggressive braking straight after driving off in the morning - warm up the discs first)
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Old 3rd May 2014, 09:57   #22
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Default Re: Brakes - A few tips that could help

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Originally Posted by sagarpadaki View Post
The discs need to be changed...if the thickness of the disc has worn below the min threshold value. This is measured using a vernier caliper in the service center.
Quote:
Originally Posted by VeyronSuperSprt View Post
...change the discs... The service limit is prescribed by the manufacturer and will be available with the ASS. As a rule of thumb, the discs would need to be changed at every third replacement of the brake pads.
How does one decide on the service limit / minimum threshold value?

I have not yet come across any manufacturer's workshop manual that recommends such a threshold / limit value for discs.

Could anyone please highlight some such numbers by any OE manufacturer where the recommended thickness of the discs after skimming is described as xx millimeters or xx% of the original thickness?
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Old 3rd May 2014, 10:53   #23
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Default Re: Brakes - A few tips that could help

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Originally Posted by SS-Traveller View Post
How does one decide on the service limit / minimum threshold value?

I have not yet come across any manufacturer's workshop manual that recommends such a threshold / limit value for discs.

Could anyone please highlight some such numbers by any OE manufacturer where the recommended thickness of the discs after skimming is described as xx millimeters or xx% of the original thickness?
For discs you do not have to look at the workshop manual. Just check the rear of the discs - the minimum thickness will additionally be stamped at the rear in most cases.
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Old 3rd May 2014, 11:04   #24
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Default Re: Brakes - A few tips that could help

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Originally Posted by VeyronSuperSprt View Post

Judder

Judder is when there is a shuddering sensation on the brake pedal when you apply the brakes.
I routinely get a Judder on my Figo equipped with ABS, this happens whenever there is hard braking, as well as when there is an interchange on the driving surface (Tar to gravel or sand) with simultaneous braking.

This was the first car with ABS i drove, and so assumed it has something to do with the ABS.

Now i'm having second thoughts.
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Old 3rd May 2014, 11:14   #25
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Default Re: Brakes - A few tips that could help

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I routinely get a Judder on my Figo equipped with ABS, this happens whenever there is hard braking, as well as when there is an interchange on the driving surface (Tar to gravel or sand) with simultaneous braking.

This was the first car with ABS i drove, and so assumed it has something to do with the ABS.

Now i'm having second thoughts.
Not to worry. That is just your ABS kicking in. It isnt judder at all.
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Old 3rd May 2014, 18:53   #26
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Default Re: Brakes - A few tips that could help

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Originally Posted by VeyronSuperSprt View Post
As you say the car is absolutely smooth at all speeds, there is no point in doing the balancing with the chances of spoiling a good setting.

In order to reduce the judder it would be advisable to try aggressive braking a few times as suggested earlier. Aggressive braking will reduce the intensity of any judder. If it is minor, it could remove the judder completely too. If your judder still exists after the aggressive braking exercise, then the only remedy will be to have the discs changed. (Note: Do not do the aggressive braking straight after driving off in the morning - warm up the discs first)
I had a 225 kms drive on the highway today. It was more or less empty in the afternoon. I can confirm again that there is no vibration at any speeds. Even at higher speeds. Juddering is minor once i apply brake at 120 up speeds. As you told to try out aggressive braking once or twice when the brakes get warmed up. I tried that but still the minor juddering exists. Now i have decided in the next service i will replace the brake pads, disks and rotors.
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Old 4th May 2014, 21:01   #27
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Default Re: Brakes - A few tips that could help

I have a swift ZXI and I did experience something like a huge vibration of sort when I braked hard at 120, its always there. I asked about this in service centre and they checked the brakes and said everything is fine.

I experienced this only during hard braking at high speeds and initially I thought something wrong with the alignment. But now I guess it is nothing to do with wheel alignment. Experts what you feel?

And what is the ideal time to change your brake pads? does it depend on our driving style or it is best to go with the manufacturer recommended change interval?
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Old 4th May 2014, 21:20   #28
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It just might be the abs kicking in.

Try pressing the pedal to the metal (brake) at speeds of 20-30 km/hr
If it's the same, then it's normal.

The service centre will tell you the amount of mm left on the brake pad. You can go with that whenever you get your car serviced.
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Old 5th May 2014, 08:47   #29
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Default Re: Brakes - A few tips that could help

Once a year or so - and immediately if you suspect brake pedal going very low - with car idling at stationary apply full brake pressure and hold the brake pedal down. It should hold and not "sink" down. If it sinks then there is fluid leak in the lines and needs urgent attention.
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Old 7th May 2014, 11:25   #30
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Default Re: Brakes - A few tips that could help

The brakes on swift ZDI might be better than say a L or a V variant, but they are not exactly one of the better setups available. Do compare with some other cars . I also own a Ertiga ZDI & believe me it has a much better bite than the swift. For this issue , the service centre guys have no solution, but to bleed , reflash the ECM , once they also reflashed the BCM (body control module) which had some error codes, but to no avail.
The exact problem is that the pedal requires extra force & is hard sometimes( not always). I have asked them to check or maybe replace the brake booster( I was ready to pay for the same, even under warranty).I am seriously thinking of better rally grade disc pads or maybe the discs also like DBA or Hawk pads.Actually the high torque diesels do need all 4 disc brake set ups like in the Hyundai i20 & verna.
Also, I read somewhere that despite having almost everything same, the ertiga has larger rear brake drums than swift , which may contribute to better brake capability. These are my opinions & you all are welcome to share your thoughts. Do guide me what can I try to improve the brake feel.
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