X6 Brake Issue

[X6 user]

Have anyone notice or have the some problem that the brake system in X6 is not as good as in X5? I need to apply more pressure in X6, whereas in X5, is less effort. I sent to AB for checking and they told me is normal due to their own system set up is different from the rest. :hmmmm2:

 

[kawei]

Have anyone notice or have the some problem that the brake system in X6 is not as good as in X5? I need to apply more pressure in X6, whereas in X5, is less effort. I sent to AB for checking and they told me is normal due to their own system set up is different from the rest. :hmmmm2:

A bit weird. I have both car and didn't notice much difference in pedal feel.
In fact, X6's brake is shaper as the car body is lighter while sharing same brake pump & calipers.
1. Please check your brake pump for leakage
2. Replace your rubber brake hose with the stainless steel brake hose.
3. Have your brake disc drilled, make sure its done using CNC machine

 

[B33mEr]

A bit weird. I have both car and didn't notice much difference in pedal feel.
In fact, X6's brake is shaper as the car body is lighter while sharing same brake pump & calipers.
1. Please check your brake pump for leakage
2. Replace your rubber brake hose with the stainless steel brake hose.
3. Have your brake disc drilled, make sure its done using CNC machine

If you were to suggest that in e46fanatics, bfc or over at sixspeed you would be lynched for suggesting such a thing. Drilling the disc would affect it's metal properties and increase metal fatigue and not to mentioned the possibility of developing hairline cracks. Cross drilling brakes is only done at the manufacturing plant as intended.
Plus how does one cross drill the brake disc solve the OP's problem???

 

[kawei]

If you were to suggest that in e46fanatics, bfc or over at sixspeed you would be lynched for suggesting such a thing.

This is BMW Club Malaysia.

Drilling the disc would affect it's metal properties and increase metal fatigue and not to mentioned the possibility of developing hairline cracks. Cross drilling brakes is only done at the manufacturing plant as intended.
Plus how does one cross drill the brake disc solve the OP's problem???

It depends on the workmanship of drilling, i've done mine for all my car, front & rear with original disc, it solve alot of my problem. Brake pad & disc would last longer & less brake fade due to better thermal efficiency, this might be one of the reason why the pedal feel is softer.

To address the possibilities of hairline crack, make sure the surface have bigger hole then the inner hole when you drill your disc, imagine drilling the hole like a cone shape. ie 5mm outside with 3mm inside, the difference is covered using a 45 degree slope.

 

[B33mEr]

This is BMW Club Malaysia.

Way to go Capt. Obvious ...

It depends on the workmanship of drilling, i've done mine for all my car, front & rear with original disc, it solve alot of my problem. Brake pad & disc would last longer & less brake fade due to better thermal efficiency, this might be one of the reason why the pedal feel is softer.

To address the possibilities of hairline crack, make sure the surface have bigger hole then the inner hole when you drill your disc, imagine drilling the hole like a cone shape. ie 5mm outside with 3mm inside, the difference is covered using a 45 degree slope.

Te steps you describe above still doesn't eliminate the danger of hairline cracks. What you are referring to is called chamfering. it still doesn't eliminate hairline cracks and dangerous if not done properly by a workshop as you describe. If you still want cross drilled then do get the one offered from BMW or aftermarkets such as brembo and etc ... At least you know they're done right and have passed QC

- notice the crack?

Also modern disc are ventilated already and i really doubt the soft spongy feel is because of the heat as the OP did not say he was driving the car aggressively ... It could just be that he need to bleed the brake line again or as you said could be the brake pump.

 

[kawei]

Hairline crack can't be eliminate completely. Even OE Ferrari front brake disc also develop hairline crack for arguement sake. You might contact Naza Italia and find out

Vented disc is not too common yet in modern vehicle of Malaysia.
E class (W211 & 212) 5 series (E60) & X series ( E53, 70 & 71) all doesn't come with vented disc. This is true for non AMG or M version.

Brake related problem is common amongst heavy vehicle especially SUV, it is therefore good to start with vented brake disc as its the cheapest solution before opting for BBK.

 

[B33mEr]

Hairline crack can't be eliminate completely. Even OE Ferrari front brake disc also develop hairline crack for arguement sake. You might contact Naza Italia and find out

Vented disc is not too common yet in modern vehicle of Malaysia.
E class (W211 & 212) 5 series (E60) & X series ( E53, 70 & 71) all doesn't come with vented disc. This is true for non AMG or M version.

Brake related problem is common amongst heavy vehicle especially SUV, it is therefore good to start with vented brake disc as its the cheapest solution before opting for BBK.

Doesn't come with vented disc ... really??? That's funny cos my old e46 comes with vented disc :- http://realoem.com/bmw/showparts.do?model=EV52&mospid=47644&btnr=34_0758&hg=34&fg=07

So does the E60 too :- http://realoem.com/bmw/showparts.do?model=NE52&mospid=48462&btnr=34_1325&hg=34&fg=07

the same with X5 (E53) MY2000 :- http://realoem.com/bmw/showparts.do?model=FB32&mospid=47741&btnr=34_0976&hg=34&fg=07

Where do you get your facts??? Anyway the point is cross drilling on a used rotors is just down right dangerous and should not be considered at all unless it was purchased new from disc manufacturer e.g zimmerman, brembo, stoptech and have QC test and NOT by a workshop on a already used blank rotors ...

 

[Herbert]

Even my e39 525i local CKD model come front & rear ventilated disc. I fully agree that one should never cross drill on used or even new rotors. But I guess some local workshops will tell you a very convincing story without telling you the risk involved.

 

[kawei]

Doesn't come with vented disc ... really??? That's funny cos my old e46 comes with vented disc :- http://realoem.com/bmw/showparts.do?model=EV52&mospid=47644&btnr=34_0758&hg=34&fg=07

So does the E60 too :- http://realoem.com/bmw/showparts.do?model=NE52&mospid=48462&btnr=34_1325&hg=34&fg=07

the same with X5 (E53) MY2000 :- http://realoem.com/bmw/showparts.do?model=FB32&mospid=47741&btnr=34_0976&hg=34&fg=07

Where do you get your facts??? Anyway the point is cross drilling on a used rotors is just down right dangerous and should not be considered at all unless it was purchased new from disc manufacturer e.g zimmerman, brembo, stoptech and have QC test and NOT by a workshop on a already used blank rotors ...

Sorry for my mistake. It come vented but without drilling.
Drilling to be perform on new set of disc.
One might disagree, but my i've got positive experience with cross drilling.

 

[kawei]

Even my e39 525i local CKD model come front & rear ventilated disc. I fully agree that one should never cross drill on used or even new rotors. But I guess some local workshops will tell you a very convincing story without telling you the risk involved.

I fully understand the risk associated with it. In fact, I'm very reluctant until i tried it last year.
Since then almost all the car in my house sent for drilling.

 

[2wenty6]

Is there truly a need for drilling the rotors? I mean...brake fade on public roads? Really now... Even the M cars don't come with drilled rotors.
There are many things that can be done to address the soft pedal feel BEFORE resorting to backyard modification.

But that, is of course, just my opinion. :top:

 

[kawei]

Is there truly a need for drilling the rotors? I mean...brake fade on public roads? Really now... Even the M cars don't come with drilled rotors.
There are many things that can be done to address the soft pedal feel BEFORE resorting to backyard modification.

But that, is of course, just my opinion. :top:

That is just my personnel preference.:love:

Yes, brake fade on public road especially SUV You are braking a 2.3 tonnes truck.

 

[B33mEr]

That is just my personnel preference.:love:

Yes, brake fade on public road especially SUV You are braking a 2.3 tonnes truck.

You would think that BMW engineers (which is one of the best in the industry) would have tested the brakes to it's maximum capacity at it's test facilities and at a track like Nurburgring no less ... Like bro 2wenty6 mentioned there are other ways to address it before resorting to a backyard modification.

 

[kawei]

I believe BMW engineer do take most technical issue into consideration but not attitude
ie braking from 180 km/h down to 80 km/h as a lorry just hog the overtaking lane, sounds familiar?

 

[Alex5522]

Take a try to change the brake pad as far i know Bendix Brake Pad was not bad. Being using on my previous Land Cruiser Ninja 4.2 VX-Limited in Sabah.

 

[2wenty6]

I believe BMW engineer do take most technical issue into consideration but not attitude
ie braking from 180 km/h down to 80 km/h as a lorry just hog the overtaking lane, sounds familiar?

I'll try not to be snarky here, but I think manufacturers have more foresight than that. Designing of the braking system isn't just a bunch of engineers sitting around drinking beer and doing calculations on their computers.

The only reason I'm posting is because if there is one system on the car you don't wanna fool around with it will be your brakes, so other members who stumbled upon this thread will at least have an idea of the misconception you're spewing. The fact is this, having holes affect the structural integrity of the rotors. Especially so if it is drilled, because drilling will introduce micro cracks and create stress points. How is it different from reputable brands selling drilled rotors you ask? Those holes are actually cast during the manufacturing process. It isn't drilled AFTER the rotor is produced - which eliminates the micro cracks and stress points introduced when drilling.

If cross-drilled rotors are so good, why doesn't the M cars come equipped with them. Too expensive? The floating rotors themselves aren't cheap. Why aren't F1 cars equipped with cross-drilled rotors?

I hope you don't feel that this is directed towards you personally, it just happened that you raised this point and I hope others could make an educated choice if they were to refer to this thread. Our forum isn't exactly a gold mine of technical information so I'm just doing my part to contribute.

At the end of the day, it really doesn't bother me if someone is adamant about drilling their rotors, be it new blanks or used rotors. It is their car, their money, their family's lives that they're jeopardizing. If you can afford an X6 you can afford better brakes (if need be). But my opinion stands, there are many things that can be done before resorting to modifying your rotors - and even then, the rotors shouldn't be drilled.

I'm just a guy from the internet, do what makes you sleep better at night. :top:

 

[pratt]

I'll try not to be snarky here, but I think manufacturers have more foresight than that. Designing of the braking system isn't just a bunch of engineers sitting around drinking beer and doing calculations on their computers.

The only reason I'm posting is because if there is one system on the car you don't wanna fool around with it will be your brakes, so other members who stumbled upon this thread will at least have an idea of the misconception you're spewing. The fact is this, having holes affect the structural integrity of the rotors. Especially so if it is drilled, because drilling will introduce micro cracks and create stress points. How is it different from reputable brands selling drilled rotors you ask? Those holes are actually cast during the manufacturing process. It isn't drilled AFTER the rotor is produced - which eliminates the micro cracks and stress points introduced when drilling.

If cross-drilled rotors are so good, why doesn't the M cars come equipped with them. Too expensive? The floating rotors themselves aren't cheap. Why aren't F1 cars equipped with cross-drilled rotors?

I hope you don't feel that this is directed towards you personally, it just happened that you raised this point and I hope others could make an educated choice if they were to refer to this thread. Our forum isn't exactly a gold mine of technical information so I'm just doing my part to contribute.

At the end of the day, it really doesn't bother me if someone is adamant about drilling their rotors, be it new blanks or used rotors. It is their car, their money, their family's lives that they're jeopardizing. If you can afford an X6 you can afford better brakes (if need be). But my opinion stands, there are many things that can be done before resorting to modifying your rotors - and even then, the rotors shouldn't be drilled.

I'm just a guy from the internet, do what makes you sleep better at night. :top:

It's people like you that makes people like me coming back to a forum like this. A very diplomatic response for all to agree to disagree have a good Friday everyone, drive safe and enjoy your ride.

 

[B33mEr]

I'll try not to be snarky here, but I think manufacturers have more foresight than that. Designing of the braking system isn't just a bunch of engineers sitting around drinking beer and doing calculations on their computers.

The only reason I'm posting is because if there is one system on the car you don't wanna fool around with it will be your brakes, so other members who stumbled upon this thread will at least have an idea of the misconception you're spewing. The fact is this, having holes affect the structural integrity of the rotors. Especially so if it is drilled, because drilling will introduce micro cracks and create stress points. How is it different from reputable brands selling drilled rotors you ask? Those holes are actually cast during the manufacturing process. It isn't drilled AFTER the rotor is produced - which eliminates the micro cracks and stress points introduced when drilling.

If cross-drilled rotors are so good, why doesn't the M cars come equipped with them. Too expensive? The floating rotors themselves aren't cheap. Why aren't F1 cars equipped with cross-drilled rotors?

I hope you don't feel that this is directed towards you personally, it just happened that you raised this point and I hope others could make an educated choice if they were to refer to this thread. Our forum isn't exactly a gold mine of technical information so I'm just doing my part to contribute.

At the end of the day, it really doesn't bother me if someone is adamant about drilling their rotors, be it new blanks or used rotors. It is their car, their money, their family's lives that they're jeopardizing. If you can afford an X6 you can afford better brakes (if need be). But my opinion stands, there are many things that can be done before resorting to modifying your rotors - and even then, the rotors shouldn't be drilled.

I'm just a guy from the internet, do what makes you sleep better at night. :top:

Very well said and spot on bro :top:

 

[LiteBulb]

self-drilled rotors, sounds as dangerous as lowering the ride by cutting the springs.....