Next time get Raybestos Advanced technology rotors...they come with a nice anti-corrosion coating for less $$$
Look at my rotors, all this rust normal?
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A co-worker has a C6 'vette with those open-spoke wheels that are so popular now where you can see is acres of rotor between the spokes- his develop visible surface rust within an *hour* of him parking the car on a rainy day. But its still just a trace of rust by the end of the day-not big honkin' flakes like that.
I'd say you got some very low-quality (made in China?) rotors there, because I've NEVER seen that much on a daily-driven car. Not all cast iron is the same- the trace metals (nickel, zinc, chromium, etc) used in the alloy can make a huge difference in the hardness, heat resistance, and (yes) how fast the rust develops and how thick it gets. These "trick" cross-drilled aftermarket rotors tend to be some of the worst IMO.
I'd say you got some very low-quality (made in China?) rotors there, because I've NEVER seen that much on a daily-driven car. Not all cast iron is the same- the trace metals (nickel, zinc, chromium, etc) used in the alloy can make a huge difference in the hardness, heat resistance, and (yes) how fast the rust develops and how thick it gets. These "trick" cross-drilled aftermarket rotors tend to be some of the worst IMO.
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Kestas
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I used to work in a prototype casting shop within Chrysler, which included making rotors and qualifying rotors from other foundries. Foundry practices have as big an impact on cast iron hardness as alloy content. Some of you are making too big a deal out of rotor cast iron metallurgy without any evidence to back it up, especially with regards to corrosion. ALL cast iron corrodes horribly.
The only practical way to deal with rotor corrosion is to buy rotors with a coating, paint them, or just live with the corrosion.
There's nothing you can do about corrosion on the working rotor surface except to either garage the car in a non-humid environment or periodically give the car some exercise.
Skylinegtr never did report whether the overnight rust came off the working surface after a trip.
The only practical way to deal with rotor corrosion is to buy rotors with a coating, paint them, or just live with the corrosion.
There's nothing you can do about corrosion on the working rotor surface except to either garage the car in a non-humid environment or periodically give the car some exercise.
Skylinegtr never did report whether the overnight rust came off the working surface after a trip.
Originally Posted By: demarpaint
Completely normal. I see you live in Queens, I'm in Valley Stream, sometimes I can actually smell the salt water smell from the south shore beaches. What you're seeing is typical flash rusting. When I worked over at a Local Honda Dealership there were cars that would sit overnight and get that rust coating on the rotors. Some flash rusted faster than others but just about all of them looked like yours. Other than priming and painting the hub all you can do is live with it.
That was my first thought as well. Some flash rust is totally normal. You can avoid some of it by only cleaning the friction surface (when you use brakleen at installation), or you can paint non-friction surfaces.......
...OR you can make doubly-sure you don't park in a spot where your car will be in a salty sea-breeze!
Completely normal. I see you live in Queens, I'm in Valley Stream, sometimes I can actually smell the salt water smell from the south shore beaches. What you're seeing is typical flash rusting. When I worked over at a Local Honda Dealership there were cars that would sit overnight and get that rust coating on the rotors. Some flash rusted faster than others but just about all of them looked like yours. Other than priming and painting the hub all you can do is live with it.
That was my first thought as well. Some flash rust is totally normal. You can avoid some of it by only cleaning the friction surface (when you use brakleen at installation), or you can paint non-friction surfaces.......
...OR you can make doubly-sure you don't park in a spot where your car will be in a salty sea-breeze!
A friend of my who teaches auto repair at BOCES (tech high school in NY) tried an expensive rotor on one side and a bargain one on the other side of a vehicle they worked on. After a year both looked pretty [censored].
His view is to replace rotors with every brake pad change and you will be better off. I think he said he did not even fix a brake lathe that broke as its not cost effective to resurface rotors.
I have rust on my Jeep's rear rotors since there is a horizontal surface to do with the parking brake shoe area outside. The rotor surface is always shiny but not this area.
His view is to replace rotors with every brake pad change and you will be better off. I think he said he did not even fix a brake lathe that broke as its not cost effective to resurface rotors.
I have rust on my Jeep's rear rotors since there is a horizontal surface to do with the parking brake shoe area outside. The rotor surface is always shiny but not this area.
I found a picture of when I had the OEM rotors. There's like no rust on the hat.
That's awful. I get minor rust after a week, and a surface coating of rust if it's really humid.
Building up that kind of rust is going to eat your pads in short order and probably eventually pit the rotors.
Building up that kind of rust is going to eat your pads in short order and probably eventually pit the rotors.
Do the new rotors perform better than the OEM rotors... or just look nicer when you are at a red light ?
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The new rotors perform better than you get some heat on them with the hawk hps pads. The OEM were garbage as they were warped in under 5k. Had them resurfaced and warped again within 5k. Other M owners reported the same problem and never went with OEM rotors.
The OEM rotors were warped so badly that light braking would make the steering wheel shake left and right. At highway speed it would be even scarier and you feel like you have no control of the car.
The OEM rotors were warped so badly that light braking would make the steering wheel shake left and right. At highway speed it would be even scarier and you feel like you have no control of the car.
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I just noticed that the pads don't completely cover the sweep area of the rotor. Is this as it should be?
Very normal, however, my 19 year old BMW has the original rotors on it and they have no rust anywhere.
Mine don't either. IIRC, any car I have ever had always has about 1/2 inch or so of unused rotor near the hub.
Originally Posted By: skylinegtr
The new rotors perform better than you get some heat on them with the hawk hps pads ... The OEM rotors were warped so badly that light braking would make the steering wheel shake left and right
The only way to accurately diagnose a warped rotor is with a runout gauge. Without that, the shaking you felt was in all probability a result of the oem pads leaving deposits, not the metal warping. The fact that you no longer experience this shaking is most certainly the HPS pads, not the rotors.
Here is a much better description than I can offer:
http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml
The new rotors perform better than you get some heat on them with the hawk hps pads ... The OEM rotors were warped so badly that light braking would make the steering wheel shake left and right
The only way to accurately diagnose a warped rotor is with a runout gauge. Without that, the shaking you felt was in all probability a result of the oem pads leaving deposits, not the metal warping. The fact that you no longer experience this shaking is most certainly the HPS pads, not the rotors.
Here is a much better description than I can offer:
http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml
I don't know about frozen rotors, but I have seen a ton of these websites that come out where these companies just buy cheap rotors and drill them, actually weakening them.
For a street car you don't need drilled rotors. I have seen cars where the rotor will actually crack in between the drill holes.
The solid rotor would have been better.
I have found that the factory rotors on many cars are excellent. For that car, I would think the factory rotors are over $100 each.
For a street car you don't need drilled rotors. I have seen cars where the rotor will actually crack in between the drill holes.
The solid rotor would have been better.
I have found that the factory rotors on many cars are excellent. For that car, I would think the factory rotors are over $100 each.
Originally Posted By: JustinH
I don't know about frozen rotors, but I have seen a ton of these websites that come out where these companies just buy cheap rotors and drill them, actually weakening them.
Same here, plus I've been on SOOO many forums where people buy these and then can't wait to throw them in the trash 6 months later. There ARE good cross-drilled rotors out there, but personally I see no need for them in any application where they weren't stock, with the possible exception of certain cars that have badly under-sized brakes to start with. "Cross drilled" is right up there with "billet" on the list of genuine engineering terms and features that have been glommed onto by marketers and hucksters.
I don't know about frozen rotors, but I have seen a ton of these websites that come out where these companies just buy cheap rotors and drill them, actually weakening them.
Same here, plus I've been on SOOO many forums where people buy these and then can't wait to throw them in the trash 6 months later. There ARE good cross-drilled rotors out there, but personally I see no need for them in any application where they weren't stock, with the possible exception of certain cars that have badly under-sized brakes to start with. "Cross drilled" is right up there with "billet" on the list of genuine engineering terms and features that have been glommed onto by marketers and hucksters.
Originally Posted By: paulo57509
I just noticed that the pads don't completely cover the sweep area of the rotor. Is this as it should be?
Every car I have ever work on the pads don't cover 100% of the rotor.
However, some designs cover more of the rotor than others.
I just noticed that the pads don't completely cover the sweep area of the rotor. Is this as it should be?
Every car I have ever work on the pads don't cover 100% of the rotor.
However, some designs cover more of the rotor than others.
These rotors won't rust. www.reddevilbrakes.com/page/page/1001014.htm
Originally Posted By: artificialist
Originally Posted By: paulo57509
I just noticed that the pads don't completely cover the sweep area of the rotor. Is this as it should be?
Every car I have ever work on the pads don't cover 100% of the rotor.
However, some designs cover more of the rotor than others.
I'm just asking because the innermost holes aren't even covered by the width of the pads.
Originally Posted By: paulo57509
I just noticed that the pads don't completely cover the sweep area of the rotor. Is this as it should be?
Every car I have ever work on the pads don't cover 100% of the rotor.
However, some designs cover more of the rotor than others.
I'm just asking because the innermost holes aren't even covered by the width of the pads.
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