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Old 1st May 2014, 11:17   #1
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Default Brakes - A few tips that could help

I guess we would all agree that it is the brakes that actually help us go faster more than a powerful engine would. For the simple reason that if we do not have good brakes we would not have the confidence to carry higher speeds even with a powerful engine under the hood. Yet, most of the time we take the brakes for granted and do not give them any special care. Here are a few simple tips that will help you make your brakes more effective, prolong it’s life and hopefully, sort out a few problems too.

Bedding in of a new car’s brakes

A new car’s brakes need to be “bedded-in” which means that you need to help the rotors and pads work in tandem properly. A proper bedding-in will result in a longer life and more effective brakes.

Bedding-in is done by being careful about how you apply the brakes during the first 250 – 300 kms. All braking during this period must be gradual / gentle braking. Avoid hard braking and certainly all panic braking. The brakes in a new car will have a reduced braking effect during this bedding-in period which means that you may have to apply a slightly higher pressure on the brake pedal.

If you live in an extremely crowded area, then bedding in is not going to be an easy task so what you can do is take the car out on long drives early in the morning onto the highway or other clear stretch of road and let the kms pile up so that you reach the 250-300 km target.

Bedding – in of New Pads / Rotors after installation

New Pads / Rotors that have just been installed on your car have also to be bedded in for the initial 250-300 kms and all the precautions that are applied to a new car as indicated above apply.

Warm up before a fast /long distance drive

Warming up the brakes is especially important before you go on a high speed /long distance drive where you could apply cold brakes for the first time at 120 – 140 kmph with chances that the sudden change in temperature could warp your rotors resulting in juddering of your brakes.

Warming up the brakes can be done by braking from 40/60/80 kmph to 20/40/60 kmph a few times. (2 or 3) Apply moderate pressure during this braking (not too hard nor too gentle).This should get the rotors and pads warmed for your high speed drive.

Caution: (1) Ensure to do this after checking that you do not have traffic behind you, and (2) Do not allow the car to come to a complete stop during the warm up.

Judder

Judder is when there is a shuddering sensation on the brake pedal when you apply the brakes. Initially this shuddering sensation will be felt only during high speed braking. If this is left unattended, the shuddering will also be felt at low speeds along with a higher intensity shuddering at higher speeds. The next stage is when the higher intensity shudder will also be felt on the steering wheel. Leaving this unattended will result in severe damage to the suspension and steering components.

The causes of judder are many including:

(a) Defective rotors / pads
(b) Wrong fitment
(c) A very gentle style of braking which does not remove the dust / rust accumulated on the rotors.
(d) Not drying the brakes after a wash and applying brakes at high speed with the rust still on the rotors.
(e) Sudden application of brakes at high speed when the brakes are still cold (described earlier)

If the judder is minor, it may be possible to eliminate the judder by some aggressive braking after warming up the brakes as indicated in the earlier paragraph. This is to be done after warming up the brakes. The aggressive braking helps dislodge the rust / dirt and other particles that have accumulated and which is one of the reasons for judder. If the judder does not go away with this, then the only remedy would be to change the discs and pads.

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.

After washing your car

After you wash your car, take it for a short spin and apply the brakes so that the water does not remain on the discs or drums. While applying the brakes for such drying do not allow the car to some to a complete stop. Even after doing this, it is possible that some water remains on the pads which can be removed by some moderate braking on your next drive.

If you have not been able to take the car out for spin after a wash, then some moderate braking on your next drive will help clear the rust.

If the brakes are stuck

On occasion, if you do not remove the water from the brakes it can lead to your brakes getting stuck. This usually happens on the rear drums and its indication is the car hesitating to move when you put it in first gear. If this is the case, do not move the car but give 2 or 3 hard taps on the drums with a wheel spanner . This will dislodge the stuck brake drum and the car will move freely. There may be a small scraping sound and this will disappear after some distance.

After driving through water

If you have traveled through water, do not continue driving without drying the brakes. Drying the brakes can be done by applying moderate pressure so that your brake effectiveness is restored.

Happy Motoring!

Last edited by VeyronSuperSprt : 1st May 2014 at 11:20.
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Old 1st May 2014, 11:49   #2
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Default Re: Brakes - A few tips that could help

Driving cautiously/drying brake pads, after driving through water or car wash is OK and mentioned in car manuals too, but some other items (not all) as posted above, IMO not at all required.
Warming up brakes before long drive is absolutely crap theory. A car running on highway for long periods without any brake usage, will have it's rotors attain ambient temperature (+wind chill) in no time. To keep them warm we would need to keep applying brakes every 5 minutes or so.
I think being car enthusiasts is one thing, but sometimes we tend to go overboard, pampering our rides too much than required, like changing engine oils before the recommended interval, applying car coatings, etc
This not only puts an unnecessary financial burden, it robs off drving pleasure too sometimes, like this brake warming exercise.
But then each one has his/her own experiences and beliefs and i respect them.

Last edited by chaudh2s : 1st May 2014 at 12:14.
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Old 1st May 2014, 11:58   #3
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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. Initially this shuddering sensation will be felt only during high speed braking. If this is left unattended, the shuddering will also be felt at low speeds along with a higher intensity shuddering at higher speeds. The next stage is when the higher intensity shudder will also be felt on the steering wheel. Leaving this unattended will result in severe damage to the suspension and steering components.

The causes of judder are many including:

(a) Defective rotors / pads
(b) Wrong fitment
(c) A very gentle style of braking which does not remove the dust / rust accumulated on the rotors.
(d) Not drying the brakes after a wash and applying brakes at high speed with the rust still on the rotors.
(e) Sudden application of brakes at high speed when the brakes are still cold (described earlier)

If the judder is minor, it may be possible to eliminate the judder by some aggressive braking after warming up the brakes as indicated in the earlier paragraph. This is to be done after warming up the brakes. The aggressive braking helps dislodge the rust / dirt and other particles that have accumulated and which is one of the reasons for judder. If the judder does not go away with this, then the only remedy would be to change the discs and pads.

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.

Thanks a lot for sharing its indeed a very helpful topic.

I own a Etios petrol and has done around 31,000kms. I had a problem of juddering if i use the brake above 140. Later the juddering came down to speeds around 100. I complained at Toyota service center. I asked them to change the brake pads and the disks too. But they checked for any any kind of bend or unevenness on the disks and confirmed it to be fine. Even according to them the original brake pads were fine at 30,000kms. What they told is there were some dusts which they cleaned and told me it should be fine. After getting the servicing done i drove the car on the highways. At speeds around 100 the juddering is gone when i apply the brakes but at 120 up speeds its still there but have reduced significantly and is minor now.

I asked my local mechanic about this and according to him there must be a minor bend/unevenness on the disk which they failed to identify on there machine. His statement is i should either replace the brake pads and disks or give the brake disk to lathe. But Toyota is insisting on not doing anything and strictly avoid giving for lathe and they are confident its fine. According to them now the minor juddering which is coming above 120 will not do any harm to the car.

But what you wrote in the above post that juddering can cause harm to the suspension and steering column is 100% true. But service center guys are saying the juddering in my car is so minimum that it wont do any harm. Still am skeptical to believe them as the juddering is present. It may be minor but it will definitely harm the other components like suspension and steering column though in a smaller extent.

So what i do now is i try to use minimum braking above 120, i bunk more on engine braking or i leave the accelerator earlier anticipating for longer distance. Though the juddering is now minor i still feel a bit irritated as i love to maintain all the mechanical's of my car in a 100% perfect way.


I just want to add one more point on brakes from my personal experience-

Do not keep your car on hand brakes for a longer period. Specially in monsoons. Earlier in our Fiat Uno we had an experience of the rear brakes getting jammed even after releasing the hand brake. The remedy was to get down from the car and push the car side ways so it can sway side ways. It some times helped to release the brakes shoes and secondly if it do not help open the rear tyre and gently hit the rear drum. It used to do the trick.

So while parking best way is if your car is parked in a secured place just put a brick under the tyre and leave the car in neutral and do not engage the hand brakes.

Off topic I told to keep it in neutral as, if you engage in a gear the clutch plate has to bear the heat of the heated engine which reduces the life of the clutch plate. So later once the engine is cooled you can keep it in gear. But if one parks in a public place then i will suggest to either put on the hand brake or engage the gear as if any one removes the brick then the car might roll forward or reverse resulting in a mishap.

Last edited by Samba : 1st May 2014 at 12:02.
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Old 1st May 2014, 12:07   #4
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Default Re: Brakes - A few tips that could help

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But Toyota is insisting on not doing anything and strictly avoid giving for lathe and they are confident its fine. According to them now the minor juddering which is coming above 120 will not do any harm to the car.
This is something that most ASS's do. However, Insist that you want the rotors and pads replaced under warranty and that the car is not comfortable to drive at 120 kmph. Depending on the amount of pressure you put on them, they will agree to replace your pads. It is certainly not advisable to continue with the current level of judder as it will gradually increase with time.
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Old 1st May 2014, 12:15   #5
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Default Re: Brakes - A few tips that could help

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This is something that most ASS's do. However, Insist that you want the rotors and pads replaced under warranty and that the car is not comfortable to drive at 120 kmph. Depending on the amount of pressure you put on them, they will agree to replace your pads. It is certainly not advisable to continue with the current level of judder as it will gradually increase with time.

According to them brake pads and discs do not fall under warranty. The whole set including installation costs around 7.5k. Even i was ready to pay them but still they are not keen to change the parts. Its true 95% of the time i drive below 120 but still a defect is a defect. I will get it changed once it slightly increases. Thanks a lot for your advice. I will definitely keep it in mind.

Last edited by Samba : 1st May 2014 at 12:16.
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Old 1st May 2014, 12:23   #6
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Default Re: Brakes - A few tips that could help

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According to them brake pads and discs do not fall under warranty.
Brake pads and discs usually have a lower warranty - 6 months or 10,000 kms etc. Check your warranty certificate to ascertain this.
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Old 1st May 2014, 12:29   #7
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Default Re: Brakes - A few tips that could help

VeyronSuperSprt

Thanks a lot for bringing out this critical aspect of driving. I have a Fortuner, the second generation.
As pointed out by many, even the upgraded Fortuner has only a decent brake & there is scope for improvement.
This had played on my mind a lot, hence when I bought the Fortuner in July last year, I went through articles like this one and did take extra pain during initial break-in period, first 600 Km drive.

I know feel that it has really helped the brakes as you have mentioned above.
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Old 1st May 2014, 13:04   #8
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Default Re: Brakes - A few tips that could help

Hi guys, I just came back from a 1800 km drive in my Hyundai santro. We had gone on a road trip to Nepal. I just have a question regarding the brakes. After driving about 500kms the brake pedal travel increased quite a bit. Almost double than what it was before. The braking was still good with a lot of bite. I had a look at the front disc pads and they are fine. After coming back home, the car was stationary for a few days and now again the pedal travel is back to normal again. So am confused as to why it would happen

Mine is a 2010 Santro, I am the first owner and it has done 15,000 kms.

Any info or advice would be of great help as we are planning on another road trip after the monsoons.
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Old 1st May 2014, 13:05   #9
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Default Re: Brakes - A few tips that could help

I have a question. What wears your brake pads more?
1) Gentle braking with less pressure and longer stopping distance.
2) Slighly higher pressure and lower stopping distance.

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?
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Old 1st May 2014, 13:08   #10
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Also ensure the brake fluid is always topped up. If you notice the brake fluid levels dropping abnormally or the handbrake light on the dashboard comes on even ehen the handbrake is not engaged, please attend to it asap.

The handbrake engages the rear wheels and is cable driven. This is to ensure even if the brake fluid leaks out you may still be able to slow down and stop the car using the handbrake.

Replace the brake pads and liners at the specified intervals as per the car's owner manual. If you are an aggressive driver and use the brakes heavily, then replacement should be more often.

It would be good if the brakes are cleaned up after a trip through waterlogged areas or severely dusty environments as debris could hamper the braking performance.
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Old 1st May 2014, 14:24   #11
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Default Re: Brakes - A few tips that could help

Quote:
Originally Posted by amrisharm View Post
Hi guys, I just came back from a 1800 km drive in my Hyundai santro. We had gone on a road trip to Nepal. I just have a question regarding the brakes. After driving about 500kms the brake pedal travel increased quite a bit. Almost double than what it was before. The braking was still good with a lot of bite. I had a look at the front disc pads and they are fine. After coming back home, the car was stationary for a few days and now again the pedal travel is back to normal again. So am confused as to why it would happen

Mine is a 2010 Santro, I am the first owner and it has done 15,000 kms.

Any info or advice would be of great help as we are planning on another road trip after the monsoons.
Usually the brake pedal travel is less when you drive off after a wash as the rust on the rotors / drums increases the friction. However, this reduced pedal travel will become normal after a few applications of the brakes and not after 500 kms. If you are sure the brakes were still good except for the increased pedal travel, then it isn't brake fade either. If the brakes are normal now, then there isn't any air in the system either.

I would suggest you have the brakes completely checked by the ASS before you go on your next trip. Let them take it on a test drive with some aggressive braking and check whether the pedal travel increases.

Quote:
Originally Posted by Rachit.K.Dogra View Post
I have a question. What wears your brake pads more?
1) Gentle braking with less pressure and longer stopping distance.
2) Slighly higher pressure and lower stopping distance.

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?
Higher pressure will have increased wear on account of the increased friction and heat build up.
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Old 1st May 2014, 17:38   #12
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Default Re: Brakes - A few tips that could help

One more good practice is to replace brake fluid once every two years regardless of mileage. Brake fluid is hygroscopic - meaning it tends to absorb moisture. When water content in the fluid goes up, it starts to boil at a lower temperature and tends to vaporize. The fluid needs to be in liquid state for it to be effective. Its a good practice to bleed the old brake fluid out completely from the brake lines and replenish with fresh brake fluid once every two years. The stuff is very cheap anyway!

Last edited by Santoshbhat : 1st May 2014 at 17:43.
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Old 1st May 2014, 18:07   #13
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Replace the brake pads and liners at the specified intervals as per the car's owner manual. If you are an aggressive driver and use the brakes heavily, then replacement should be more often.
Thanks for the tips honeybee. Just one point - manufacturers do not specify intervals for change of pads and liners, like they do for say the filters or spark plugs. However they would specify an "Inspect and Replace" interval which is a flag for the ASS to check the pads and liners and replace if found necessary.
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Old 1st May 2014, 19:26   #14
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Default Re: Brakes - A few tips that could help

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Thanks a lot for sharing its indeed a very helpful topic.

I own a Etios petrol and has done around 31,000kms. I had a problem of juddering if i use the brake above 140. Later the juddering came down to speeds around 100. I complained at Toyota service center. I asked them to change the brake pads and the disks too. But they checked for any any kind of bend or unevenness on the disks and confirmed it to be fine. Even according to them the original brake pads were fine at 30,000kms. What they told is there were some dusts which they cleaned and told me it should be fine. After getting the servicing done i drove the car on the highways. At speeds around 100 the juddering is gone when i apply the brakes but at 120 up speeds its still there but have reduced significantly and is minor now.
Brake judder can be felt at certain speeds also if your wheels are out of balance. It takes a very keen observation to observe the balancing being out by 5 to 10 grams. The steering wont shake shake but you will get an uneasy feeling when you drive at high speeds and if the balancing is out by 5 to 10 grams. This will manifest itself into a slight judder of the brakes during high speed braking. Get the wheel balancing performed ( dynamic balancing) from a very competent guy who has a balancing machine which is high end as well as is calibrated from time to time and later check if the juddering is gone or not.

And about Toyota people mentioning that brakes do judder a little at speeds about 120, absolutely false. My car is a Swift D and even from 170 to 80 brake situations, there is no judder.

Last edited by GTO : 6th January 2015 at 19:09. Reason: Trimming super long quoted post
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Old 1st May 2014, 19:48   #15
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Default Re: Brakes - A few tips that could help

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Brake judder can be felt at certain speeds also if your wheels are out of balance. It takes a very keen observation to observe the balancing being out by 5 to 10 grams. The steering wont shake shake but you will get an uneasy feeling when you drive at high speeds and if the balancing is out by 5 to 10 grams. This will manifest itself into a slight judder of the brakes during high speed braking. Get the wheel balancing performed ( dynamic balancing) from a very competent guy who has a balancing machine which is high end as well as is calibrated from time to time and later check if the juddering is gone or not.

And about Toyota people mentioning that brakes do judder a little at speeds about 120, absolutely false. My car is a Swift D and even from 170 to 80 brake situations, there is no judder.
Toyota guys didn't say that its normal they told me its so minor in my car that i can ignore it.

Okay will get the balancing and alignment done once. As till date not for a single time wheel balancing or alignment has been done on my car. Every time during the service or at a tyre shop i get it checked they told me car is absolutely fine no need to go for alignment or balancing. 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. These too after 31,000kms on the odometer.

But as you told slight mismatch of weight can be a cause for juddering specially when Toyota could not find any bend or unevenness in the discs will get it done once and see what happens. If still it exists will get the disk, rotor and brake pads changed.

Thanks.
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