Brakes, Dealer abuse? and questions.

[StefenG]

Hey everybody, this is my first time here, but from my experience with many other vehicles, these forums seem to be the place to get the right answers to my questions, so hopefully you guys/girls can help me out.

So my mom phoned me from across the country the other day to ask me a question about her car(2008 G37s 6sp man). It has about 30,000km on it and is a daily driver. Now the dealership told her that they needed to machine her rotors because of rust build up, but that her brake pads were fine.

Now i understand that some grooving or pitting is possible even at this kind of mileage, but rust buildup on a daily driven car? I told her i thought this was ridiculous, so she asked the service manager to explain it to her when she got there.

This is part of the email she sent me:

"He told me that (apparently Volvo and BMW have the same issue) before they had discs, there was a "cover" in place, and with the disc system, it is an open system. Apparently the front caliper system gets full of "gunk" and does not put enough pressure on the brake pad which ends up making contact on one end only (angle) and the rust builds up and does not go away as the brake pad does not sit flat on it.

He does appear that it is a caliper issue, when they get "gunky" in the winter roads (gravel, salt, etc..) I still have a bit of a problem with the explanation, but he showed me a car that was already "jacked up". There was a dirty caliper and rust there, but I would not know how much rust you need to have to machine it. It seems to me that if that was the case, all they had to do was to clean the caliper (which would have been $130 cheaper) and once the brake pad made proper contact, it would have got rid of the rust by itself.

The service manager appeared surprised that I had my tires changed in October and that it built up in 3 months, but said it must be the junk on the road. ..

I looked at my car and the "caliper" has a cover on it, unlike the one he showed me in the shop. I think I got somewhat "screwed" on that one... I paid $260 for "machine front brake rotors and service calipers- 1 stop squeal kit $13 and $260 in labor" Your thoughts?"

So my questions:

1) Is the rust buildup on a daily driven car like this even possible?2)I have a hard time believing that the "gunk buildup" in the caliper is going to overcome the pressure of a four piston caliper from applying pressure to the rotor(it is a 4 piston is it not?) 3)If this is actually possible and only one part of the pad is touching enough to supply stopping pressure, on a daily driven car, would this still not keep the rotor surface clean of rust? Not to mention there would be seriously abnormal pad wear, in which case if you machined the rotors you would most likely do the pads at the same time.4)Is this an actual known problem? If it is, would this not be a safety issue? And if it is again is there a TSB regarding this issue?

I know this is a lot of questions, but i am having issues wrapping my head around this. Any light you guys can shed would be greatly appreciated.

Thanks in advance

Stefen

[telcoman]

Hey everybody, this is my first time here, but from my experience with many other vehicles, these forums seem to be the place to get the right answers to my questions, so hopefully you guys/girls can help me out.

So my mom phoned me from across the country the other day to ask me a question about her car(2008 G37s 6sp man). It has about 30,000km on it and is a daily driver. Now the dealership told her that they needed to machine her rotors because of rust build up, but that her brake pads were fine.

Now i understand that some grooving or pitting is possible even at this kind of mileage, but rust buildup on a daily driven car? I told her i thought this was ridiculous, so she asked the service manager to explain it to her when she got there.

This is part of the email she sent me:

"He told me that (apparently Volvo and BMW have the same issue) before they had discs, there was a "cover" in place, and with the disc system, it is an open system. Apparently the front caliper system gets full of "gunk" and does not put enough pressure on the brake pad which ends up making contact on one end only (angle) and the rust builds up and does not go away as the brake pad does not sit flat on it.

He does appear that it is a caliper issue, when they get "gunky" in the winter roads (gravel, salt, etc..) I still have a bit of a problem with the explanation, but he showed me a car that was already "jacked up". There was a dirty caliper and rust there, but I would not know how much rust you need to have to machine it. It seems to me that if that was the case, all they had to do was to clean the caliper (which would have been $130 cheaper) and once the brake pad made proper contact, it would have got rid of the rust by itself.

The service manager appeared surprised that I had my tires changed in October and that it built up in 3 months, but said it must be the junk on the road. ..

I looked at my car and the "caliper" has a cover on it, unlike the one he showed me in the shop. I think I got somewhat "screwed" on that one... I paid $260 for "machine front brake rotors and service calipers- 1 stop squeal kit $13 and $260 in labor" Your thoughts?"

So my questions:

1) Is the rust buildup on a daily driven car like this even possible?2)I have a hard time believing that the "gunk buildup" in the caliper is going to overcome the pressure of a four piston caliper from applying pressure to the rotor(it is a 4 piston is it not?) 3)If this is actually possible and only one part of the pad is touching enough to supply stopping pressure, on a daily driven car, would this still not keep the rotor surface clean of rust? Not to mention there would be seriously abnormal pad wear, in which case if you machined the rotors you would most likely do the pads at the same time.4)Is this an actual known problem? If it is, would this not be a safety issue? And if it is again is there a TSB regarding this issue?

I know this is a lot of questions, but i am having issues wrapping my head around this. Any light you guys can shed would be greatly appreciated.

Thanks in advance

Stefen

Welcome to NICO

I had new brake pads installed at the dealer at 85k miles. They machined the rotors at that time.What I would tell your mom is if the calipers are not sticking to just leave it alone. It is easy to check. After a short drive just place a hand on each tire. If any tire is warm then there may be a sticking caliper. Also when the vehicle is rolling slowly on level ground a sticking caliper will stop the vehicle. When I step on my clutch my vehicle will roll slowly out of my garage. A sticky caliper will show right up. Also you may want to advise your mom not to use the emergency brake when parked on level ground in the winter. Actually I rarely use it. I leave my vehicle parked in 1st gear and that will hold the car even on small inclines.I had that problem on my 92 Lexus ES300. One caliper was sticking just over the warranty at 52k miles. Lexus refused to cover it. Another sticking caliper around 100k miles. Those issues were a consideration when it came time to replace the Lexus.

I love my Infiniti. No sticking calipers thus far

Telcoman

[RED_DET]

There shouldn't be an issue with using the e-brake. It doesn't use the caliper, it has its own separate system, which uses a drum style braking system. If one of the brake calipers aren't working properly then it is possible to get build up on the surface of the rotor if pad contact is uneven. If that is the problem, then resurfacing the rotors is only a bad aid to the problem. Something is wrong with a caliper and needs attention.

[StefenG]

That's exactly my point, they went ahead and machined all four rotors and yet said all the brake pads were fine with no real service to the calipers. That's what i don't like about it..