Interesting read. Any ideas how this could have happened?

http://www.zcarblog.com/2009/04/13/e...ent-41109.html

 

New car, pads/rotors not broken in. Did they bed in the brakes?

 

EDIT: Changed my mind.

That looks like some sort of residue on the rotor. Surprised that it would not burn off with some aggressive braking. Is that just brake grease?

 

hmm, didn't know it can cause grooves on the rotors. Thought new pads would just cause green fade if not broken in?

and kinda wonder what the first problem is in this:
"I’m not going to go into what happened until we have a solution to offer all of you. After we determined that the issue wasn’t detrimental to the car or our safety we went back out in the next few sessions, and then we ran into our second problem."

 

I studied the photos and cannot see that the rotors are "cut." Looks like surface residue to me. Maybe not.

 

...and so it begins...

 

Usually when a pad grooves a rotor like that on track it's becuase the pad is gone and down to the metal rivets. Basically it's metal to metal contact resulting in sparks, loud sqealing noise and poor braking.

 

This is the second place I have seen the grooved rotor issue. The other story was MUCH worse than that. Can't remember the site now. But this is not an isolated incident, unfortunately. I'll update my post if I can find the other story on this.

 

+1. It appears to be improper track prep. Did the track day organizer require each car to be tech inspected prior to track day?

oh, I can't watch this now but they posted a vid from the day.

http://www.zcarblog.com/2009/04/15/3...l-raceway.html

<object width="560" height="340"><param name="movie" value="http://www.youtube.com/v/XWoWJ058d7c&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/XWoWJ058d7c&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="560" height="340"></embed></object>

 

Ah, here it is: Edmund's long-term test:

Definitely FTL... Not sure if the pads are too abrasive or the rotors are to soft.

Chalk it up to first year bugs

HATE this URL blocking **** tha tthis site does now. Can't link in edmunds to samve my life. check out:
can't link to the other z site either than is better than this one. FAWKING hacker ****.

GO to the other site that talks about 370z. enter domain name and then /nissan-370z-general-discussions/2175-2009-nissan-370z-long-term-test-edmunds-com.html

Their text:
This is a picture of the front rotor of our Nissan 370z after brake testing. The car had 1,000 hard miles on it, but still, after the first two stops of 130+ feet, we knew that they were not bed-in enough for testing and began that process. The bedding-in process, according to our Engineering Editor Jay Kavanagh, "establishes a useful "transfer layer" of pad material onto the rotor, and should be done on any high-performance braking systems. It works like this--you perform several (ten or so) moderate stops in rapid succession, starting from ~60 mph to ~10 mph, then let them cool." The first stops we did combined with a shortened bed-in process resulted in some screaming hot (that's a technical term) pads which became abrasive and scored the rotors. Despite the looks, the pedal feels fine and the car came to a stop from 60 in only 105 feet.

Mike Magrath, Vehicle Testing Assistant

 

The car was most certainly broken in properly. We had around 1,400 miles on the car before we took it to the track.

We took the car to the track in its stock form so that we would be able to see what any new 370z customer would experience if he or she went straight to the track with it. I know for a fact that most new owners would not go through the lengths that we have to make sure that the car was track ready.

The brake issue was not the only reason we left the track early. The other issues we experienced made calling it a day the correct choice. If the pad and rotor issue were the only problem I would have taken it out for a few more sessions to see if the problem to cleared itself.

Like I said earlier, the car had around 1,400 miles on it at this point. All of the other brakes are in perfect condition with minimal pad wear. There was no noise coming from the brake system nor was there any change in braking performance. We only discovered the issue in a post session visual inspection. It appears that the pad had just begun to disintegrate and began to grove the rotor. I picked the car up yesterday from the dealership yesterday and the parts were replaced under warranty.

The car is undergoing further modifications as we speak and we will be driving it down to southern California this weekend for the MSA 2009 show so make sure to check www.zcarblog.com for pictures and an event report.

Long Live the Z
Z Car Garage
ZCarBlog.com

 

Ok, that's clearly a grooved rotor. I haven't seen the parts, but I've experienced the phenomenon. I've had two new pads disintegrate as a result of a flaw or defect in the bonding compression process and I've had a pad completely separate from the backing plate. I think since the dealer replaced the parts under warranty and none of the other pads had a problem probably indicates it was a defect in the parts rather than the prep. If it's bad on both sides, then I'd be inclined to blame a flawed bedding-in process or poor preparation.

 

stock pads are not suitable for track use. end of story.

if track is in your future, invest in real track pads, lines, fluid and possibly better rotors.


oem is oem. we are not looking at a 30k carbon setup here.

chill people.

 

I second that, I bet they have done enough preparations then many track drivers before they went out to the track. As I personally witness the incident, (I was there with the silver Z that day), I also couldnt believe the new Z performs poorly on the race track. Brake problem, over heat issues... As a factory mechanic before, I know for a fact that most of the new release 1st generation vehicles usually have more initial problems. I have seen many cars have brake pads material problem when they first released, and when they get enough complaints, they will actually release a service bulletin to address these problems.

I really appreciated what they did to test out a 370z for us. Keep it coming!