Cross drilled rotors warped in 10 mos!

[Guest jjohart]

Hi, I have an 83 280ZXT which I replaced the rotors on with PowerSlot cross drilled rotors and metalmasters pads. It seems like 10 months or 10000 miles later and I've got warped rotors and pads worn....do ALL aftermarket pads/rotors suck this much?!!? I am wondering whether I should pay the difference and buy new Nissan pads/rotors from MidwestZ, or somewhere else that'll be cheaper than my local dealer (i.e any suggestions!?).

The other thing I was wondering is whether it is possible that my car has warped "hubs", that caused everything else to fail/wear prematurely. How does one check for this, and is this a service that a local independent mechanic would have to farm out to a specialist to fix?

Thanks

John

[blueovalz]

I don't know the website, but a posting, on proper brake pad/rotor break-in, as well as driving habits to avoid, appeared on this site some time ago. The information was very informative, and in essence makes the claim that warped rotors can be avoided. Perhaps a search will find it.

[Pop N Wood]

You definitely want to do a search on this topic. Has been discussed regularly. Some pads are much better than others. Also chances are your rotors aren't "warped" but just have an uneven layer of break pad material fused on the surface. You can probably clean them up, add a fresh set of pads and be good to go.

 

 

The break in procedure for new pads and rotors is essentially driving though a parking lot, speeding up and breaking hard without ever letting the car come to a complete stop. Start with low speeds and work your way up to faster speeds. This heats up the pads, depositing an even layer of brake pad material on the rotors. If you let the car come to a complete stop, the pads will stick to the rotor depositing a thick layer at that point.

[Guest jjohart]

It's kinda hard to say the rotors aren't warped when two mechanics have said so...exactly what kind of cleaner are you referring to?

What header/subject title should I use, as I have found the search engine here to give incredibly vague results!

Thanks

John

[Phantom]

Generally if you pull the rotors and hubs as a single unit, a good machine shop can turn them as an assembly and eliminate any tolerance accumulation run-out.

FWIW - I had to have my OEM rotors turned on my Jeep Grand Cherokee every 17,000 miles. I fixed that though. I replaced it with a Suburban.

[JMortensen]

If you want better search results, click the "search for all terms" bullet right below your keywords. That way you won't get every post that has "brakes" or "warped" in it.

 

The Powerstops I had on my car put up with AMAZING amounts of abuse. I mean AMAZING. Boiled the fluid probably 10 times, ran the fronts metal to metal twice (just barely), went through probably 6 or 7 different sets of pads, all on the same rotors, never turned them and they never warped or gave me any shudder.

 

Search for Stop Tech if you want to see that article about brake warping. It is interesting, and I believe what it says. Personally I can tell you I have had very bad experiences with Metal Masters and "warping", don't like the braking that I get from your average auto parts store pads, and have liked the Porterfield pads that I've used, although I did find that stock fronts and R4S pads are GROSSLY inadequate for any track use.

[Dragonfly]

Here's the link that Blueovalz was talking about. http://www.stoptech.com/whitepapers/warped_rotors_myth.htm

 

I think that it is very possible that Pop N Wood is correct about the pad material being stuck to your rotors and that being your problem. As far as the mechanic saying the rotors are warped... did he/they take them off the car and measure them with a test indicator or did they test drive the car and say "yep there warped". If they only did a test drive they could easily mistake a 'bump' (brake pad residue) in the rotor as the rotor being warped.

 

Read the article from the link and you will learn how to check and clean up your rotors.

 

Dragonfly

[Pop N Wood]

I don't doubt that a mechanic with a dial indicator could measure excessive run out. It also makes perfect sense that the run out could be from an uneven layer of pad material on the rotor.

 

The only question I am posing is what fix to use. If the metal of the rotors is physically warped (bent), then turning or replacing the rotors is the only real fix.

 

If the rotor run out is excessive due to a build up of brake pad material, then you can turn the rotors to retrue. But another possiblity is to clean off the excessive material and save what life you have left in the existing rotors.

 

Your call.

[scorreia]

First investigate if they are truly warped, people mentioned it because buildup is the most commonly mistaken for warping.

 

<Babble>

If they are truly warped, you are about to enter into one of the more hotly contested topics in all of car land it seems. If we are lucky, this thread could go something like this (if it hasen't already at least 50 times):

 

The science states that the crossdrilled portions are weak spots and that the mass of the rotor is also reduced. What crossdrilled rotors basically are are weaker, less efficient heat dissipating systems. Such a system would be ripe for cracking.

 

Others will say that the crossdrilling increases the surface are of the rotor so the rotor will shed heat more rapidly. Perhaps that is even true, what is left to debate is which is more important - mass or surface area? Check the math to draw your own conclusions.

 

Still even others resort to posting pictures of Porsches that come stock with crossdrilled rotors. Definitive proof if there ever was any, I wonder why those thread don't stop right there?

 

A Hotly debated discussion will ensue about whether Porsches holes are cast or drilled. If we're really lucky, we'll get a friend of a friend of an engineer whose cousin worked at Porsche actually casting them type story.

 

Someone else chimes in about their slotted rotors and how they offer the least compromise in the Mass reduction department, but still offer better wet weather and glazing resistence.

 

Another picture of a McLaren F1 makes it's debut as further proof that crossdrilled is better. Enzo's follow suit.

 

3 pages of Enzo vs F1 debate, hopefully ripe with videos.

 

Lots of people claiming AutoZone blanks are where it's at, with good pads and fluid, flushed regularly is the way to go.

</babble>

 

It seems I got ahead of myself there, that happens sometimes. I'm bored at home today.

 

Cheers

[Savage42]

As mentioned, cross drilled rotors are for looks, but are actually not a good thing for all-out performance. Wilwood highly recommends staying away from cross drilled rotors, but slotted are a good thing. The issue about high end cars having cross drilled rotors is that they are actually cast that way, which makes them much more expensive, vs the stock cast ones that people drill themselves and sell. Huge difference in quality overall. From what I've heard, Brembo doesn't even sell a cross drilled rotor, where the company buying and selling them is doing that.

 

In regards to pads, I've had bad luck with metal masters, as they have too much metal that eat rotors. The Porterfield R4S pads are awesome for street, autocross, hillclimb, & limited track duty, as they are carbon kevlar and won't eat rotors as badly. If you are doing hard track days, invest in a set of the R4 or R4E pads for those days. It's worth switching pads if you want the most out of your brakes. I had awesome luck with '82 ZX brakes w/ Porterfields on my 510, but it also weighed 2100 lbs, but seems to not be adequate to stop a boat of a ZX. Hope that helps.

[Cody 82 ZXT]

I've had good luck with the KVR pads. They've been on for about 30,000 miles and still have pad left. No dought they are not the end all be all pad but, not bad for the price and longivity. Good fluid and a real knowledge of what the ZX brakes will do once or twice but, not ten times in a row helps.

 

Can't wait to get the Wilwoods on and broken in.