pejoda

I had my dealer install EBC slotted and dimpled rotors with Akabobono ceramic pads last week. I also had them install Toyo T1R tires - standard sizes. Since then I have a constant clicking sound directly related to speed. I took the car back to the dealer who said the rear rotors had gone out of true in the 600 kilometers so they machined them and said the problem was cured. As soon as I left the dealership I heard the clicking sound again.

So now I have compromised rotors and still have the problem. I shall be taking this up with the dealer again but in the meantime has anyone experienced this?

mario23

iTrader: (10)

Slotted rotors do often make some noise.
Sounds kind of like a ten speed...

pejoda

yes - that's a good description. Is there anything that can be done about it?

mario23

iTrader: (10)

I believe that is just because of the slots and nothing can be done about it.

HyperSprite

iTrader: (6)

Mine have made a sound like described by mario23 since I put them on 8k miles ago, there is a warning on the box about it. I only notice it though when I am in the fast lane near the K rail with the windows down, as soon as the K rail is gone, I don't hear it as much and with the windows up, I don't hear it at all, regardless of the K rail.

Chris

mista350z

iTrader: (1)

my rotors made a clicking sound but only when i went real slow. it went away though after you break in the rotors a little bit. I thought something was wrong at first too. but thats just the way it is i guess.

pejoda

Thanks for the input. I researched this further and went to the EBC website and found the following in the Q and A section!

5. Intermittent noises from rotors or rotor vibration
If sport rotors are not checked for runout, driving without even applying brakes will exhibit a clicking noise on a “Once-per-rev” of the wheel basis. If you encounter this, especially early after having rotors installed return them to the service shop and have them checked for runout. Recommendations for maximum permissible runout vary from 0.001 to 0.002 inches on most European cars to 0.003 to 0.006 on larger USA Trucks and SUV’s. Figures above these are not only unacceptable but they will cause brake vibration after a period of 3000 to 4000 miles. (Read below in Blue please) which is not grounds for warranty. Mounting rotors on dirt or rust and scale covered hubs or excessive use of mounting greases and most often incorrect tightening of rotors from first install are the common reasons for excess runout. If your installer knows his job he will hand tighten the rotor studs in a diagonal fashion with gradually increasing torques by hand and final tighten with a TORQUE wrench and ideally you wont even see or hear an air gun being used. Guns (including air guns) are for cowboys and are often used by them.
Why do rotors suffer vibration after 3000-4000 miles and how can EBC be so precise in this mileage estimate, surely it cannot be the same for every car???????? … this is a common question.
The reason the mileage is more or less the same for every car where vibration occurs is that the problem develops OFF BRAKE or when you are driving without applying the brake. The more freeway driving you do the more easily this can occur. The excess runout mentioned above caused in 90% of the cases by bad fitting and not checking for runout (and the other 10% due to a hub not running true such a car that has impacted a curb at some time) … causes the pad to “Kiss” the rotor gently each revolution of the wheel as you drive. After the above mileage period the pads wear a microscopic thin spot on the rotor and a condition known as DTV occurs. This DTV (Disc Thickness Variation) causes the brake to pulse. A small amount of runout itself does NOT cause vibration but the tiniest amount of DTV does cause vibration. That is why when a rotor is not running true the car does not exhibit vibration in the first few miles and this explains how it shows up later (3000-4000 miles).
How can I cure this vibration problem ??????
Rotors will need to be turned at a machine shop or brake fitting center or replaced. EBC sport grooved rotors can be turned with good results on standard AAMCO brake lathes. If too badly scored or worn some rotors will have to be replaced. New pads will ALWAYS be needed.
Before taking your car to the shop, check if the vibration is coming from the front or the rear to save costs in unnecessary brake work. Generally vibration under braking that can be felt through the bodywork or seating of the car is a problem on the REAR brake and vibration felt on the steering wheel is related to FRONT brake problems.
What are the best pads to prevent or limit brake vibration????
Any good quality pad with a high thermal conductivity will reduce the chances of vibration both due to DTV as described above or vibration at speeds due to what we call thermal shock. Thermal shock is common on European cars and all pads in the EBC range are especially good at reducing vibration. Our online catalog recommends the minimum grades for your car and shows options.

So it seems that if this is not corrected the rotors will start a vibration after 3/4000 miles so I'm taking tghis back to the dealer 'cos in my opinion it is an installation problem that they should fix since they installed them in the first place. I'll post an update when I have met with them.

BlackSpec02

iTrader: (17)

Damn, Ive got the same clicking coming from my EBC rotors and redstuff pads.... doesnt bother me much its hardly noticable except like someone said on the freeway next to the K-rail.

I do still have the swooshing sound under braking though... ive had my ebc brakes for about 800 miles....

Q45tech

Based on millions of pads rotors miles it is often possible to predict the future.
Based on a knowledge of acoustic engineering it is possible to predict the effect of holes or slots in a rotating disk.

All of these sounds and vibrations seem to come as a shock to people who didn't finish 4 years of automotive engineering.

And worse they don't understand that the factory spent millions of dollars to engineer them out..........then they go messing [redesigning] things and bring the noises back. THEN COMPLAIN!

http://www.automotivedigest.com/Whit...etype%3Apdf%22

http://www.delphi.com/pdf/techpapers...etype%3Apdf%22

http://www.ae-plus.com/Journals/Mate...etype%3Apdf%22

Spec_Tacular

You remind me of a Doctor that speaks with a lot of terminology and expects that everyone should understand. Or the computer tech guy that thinks everyone’s is an idiot because they don't know how to reformat their hard drive. LOL

All this is just a bit of clicking because they are a slotted rotor rather then a solid one. Like most aftermarket "upgrades" there are pros and cons. That’s why it is important when changing parts on your car that you understand them prior so you can make the decision based on your personal preferences.

HyperSprite

iTrader: (6)

+1 ... and after all that " millions of pads" testing, they couldn't find a one that wasn't made out of coal dust?

Chris

pejoda

This never started out as a complaint - simply an enquiry to see if anyone else had experienced the same problem. If the manufacturer spent millions on engineering the braking system it's too bad they couldn't come up with a better braking system and then I wouldn't have to be trying to improve it myself.

Yes - windows down and running against the K rail is when it is most noticable

As it turns out my dealers mechanic never did hear the constant clicking noise that I was concerned with. What he heard was the swooshing sound that is expected under braking and he went about curing that by machining the rear rotors! But the clicking noise persisted. I had a meeting with the service manager who drove the car and he did hear the clicking and took the car in to run it with the rear wheels off the ground to see if they could locate the source of the noise. Luckily I managed to stay with the car in the shop and thats when I found out that the dealers run-out gauge was broken so they couldn't measure the run-out. I suspect it was broken before and that they got a bad reading before which caused them to do the machining. In the meantime, while the car was on the hoist, I spun the front wheels by hand and found the noise was coming from the left front wheel - not the rear wheels at all!

So after some negotiation the dealer has agreed to provide me with EBC new rear rotors. I told him - no machining! If they can't find an alternative cure, such as remounting the rotor one stud around at a time, then I might take the car elsewhere to get another opinion!

Wait for the next installment!

BlackSpec02

iTrader: (17)

good to know...

Kolia

iTrader: (2)

It think they decided for a pad that would still stop the car when it’s below freezing instead of the dustless one…

HyperSprite

iTrader: (6)

But most stock pads are a composite of good things and coal dust, Z pads are pure coal dust. There are low dust pads out there that have good cold weather bite.

My guess is they are probably the CHEAPEST material that will stop the car in most weather in a reasonable distance and last long enough that they wont be a warranty issue.

Chris

Kolia

iTrader: (2)

Cheapest was most certainly a top priority !

Q45tech

The chemicals [the 30 or so materials mixed] in every brake pad all cost the same within a dollar per pad. Don't confuse retail cost markup with having anything to do with performance. The most expensive wheel set [4 pads]might have $4 more worth of chemicals.

Copper, lead, and zinc have been reduced [eliminated] to protect street water run off into streams and lakes.

http://www.p2pays.org/ref/02/01391.p...composition%22
http://www.braungart.com/PDFs/Antimo...composition%22
http://www.transport.govt.nz/assets/...etype%3Apdf%22

If you study the details in the above you will see that Titanium dioxide/oxides is the most expensive component but it never exceeds 3% by weight.

http://www.ornl.gov/~webworks/cppr/y...etype%3Apdf%22

The above is easier to get to the heart of the matter.

As to cheapest every company in the world sends samples to try to be oem supplier

Kolia

iTrader: (2)

That looks like a very interesting paper you’ve found Q45Tech. I’ll sit down and read it as soon as I have a minute.

We must keep things in the perspective of a mass production vehicle. I’m not sure of the numbers for the Z, but let’s say a given model will be produced to 200,000 unit over a 4 year period, a saving of 10 cents a pad will make a 160,000$ difference in direct profit. If it was a full dollar (which it might be, I don’t know), that would be 1.6 million $

Every cents count for a car manufacturer. The price of a vehicle is fixed well before any type of design is started. So we can’t just “get the best stuff out there” and stay within budget.

BlackSpec02

iTrader: (17)

Right.

Q45tech

Brakes have been a nightmare for Infiniti since 1989, as they tried to win the stopping race [the 90Q stopped in magazine test in 129 feet from 60] blowing away the competition in that 4000 pound weight class.

The oem tires were the Top of the line Michelin in 1989, they wore out in < 15,000 miles but stopped and the car out handled the competition by a wide margin.

Just like today buyers didn't understand what they were buying.......oh my diety, the Q eats brake pads and tires every 15,000 miles.
Eventually they come out with pads that last a little longer and stop a little longer.

As a engineer it sometimes makes you want to make tires and brake optional and let the buyer pick their poison! without a warrranty.

You offer Brembo's and people complain, you deliver 108 foot stops and people complain.

YOU DON"T GET 108 foot stops by chosing the low cost bidder or even considering the cost on TIRES AND BRAKE PADS.