disk rotor choice

Spend the extra bucks to get the better rotors and good pads, then make sure to service and adjust the rear brakes, which in all likelihood caused the fronts to warp in the first place. Good luck, Ben

********** Excellent comment. If the rears are not functioning as they should, the mass of the braking energy will be generated at the front pads and rotors, and damage is not only likely, it is certain.

I saw a lot of this happen when GM was selling its faulty four wheel disc system. If you didnt do what you had to do to make sure the rear pads adjusted themselves, not only would the parking brake not work, but the front discs and pads would suffer.

"hls" wrote in news: snipped-for-privacy@giganews.com:

@d26g2000prn.googlegroups.com...

The fronts do appx 80% of the braking anyway so unless your a very heavy braker. the rears won`t make much diff. KB

If you dont keep the rears in adjustment, the fronts will have to do

100% of the braking. And that does make a difference.

single piston [single sided] calipers came about originally because they're more compact on the wheel side of the disk and thus make it easier to achieve negative scrub radius - something considered essential for modern sedans.

frequently supposed savings in machining single sided calipers are hard to achieve because you have to machine past the "claw", and "reliability" is negatived by two things that don't affect older style opposed piston calipers:

1. sticky sliders

1. a seized piston means the brakes don't work at all vs. opposed piston where it's rare for both to be dead.

I've had genuine FORD rotors warp in 4000 miles of normal driving. And the cheap china rotors go 20K without warping. I think it's mostly a crap shoot. I did notice the last time I bought cheap rotors that one of the ones they gave me had a crack in it near the hub and had them get me a different one. I don't think there is much difference in the amount of metal but there can be a difference in how the cooling vents are made, the size and spacing and angle. Probably doesn't matter if all you do is commute but if you regularly drive in mountainous terrain it might cause greater heat build up in the cheap ones.

Do you wash your new rotors in soap and water as the makers of the rotors say is mandatory?

I do wash them to get the rust preventative grease off of them. I have also used brake cleaner (largely methanol) in the past.

When you had the problem with the Ford rotors, was there any particular factor that you thought might have caused their early demise?

On several occasions, I have had rotors warp after having wheels rotated. These rotors had a year or two on them with no problem, but developed the warp within 2-3 weeks after the wheels were rotated and installed with an impact wrench and tork stix.

that's typical.

if you do the scrape, anti seize and proper torque thing, you'll find your rotors are probably not warped permanently, just distorted by bad seating and incorrect torque.

and tork stix are not a good choice. they make presumptions about the impulse from the air tool - if the input is not per that presumed, the output isn't either.

The experts say brake cleaner is not good enough. It won't remove the metal particles left by the machining process, only soap and water will. Supposedly it's important to remove the metal particles.

Nothing I could identify. It was a new vehicle and all work was done by the dealer and I couldn't watch what they did. The original ford rotors warped badly in 4K, the repairs (resurfaced or new, don't know which they did) lasted for even less miles. Ever since I've used the cheapest and they last much longer then the originals did. Ford want's close to $150 per rotor, the cheapies are around $50. The places that do my tires all use torque wrenches for final tightening. Myself, I have been using just an impact anymore myself (did the torque wrench thing for a while) and have not seen it cause a problem, but I adjust it to a lower power setting so it won't over-torque.

Here's the little article:

Could be.. I have never noticed any difference, really, but then this might be something I wouldn't notice. Certainly cheaper to use soap and water.

"in more than 40 years of professional racing, including the Shelby/Ford GT 40s ? one of the most intense brake development program in history - I have never seen a warped brake disc"

indeed.

this is preceded by: "presuming that the hub and wheel flange are flat and in good condition and that the wheel bolts or hat mounting hardware is in good condition, installed correctly and tightened uniformly and in the correct order to the recommended torque specification"

you will find that in most cases, simply scraping surface rust off the hub/wheel interface, applying a little antiseize, and correctly torquing fasteners will cure most "warped" disks.

the fact that disk machining also "cures" is usually due to the coincidence that cleaning is done at the same time.

disk pads contain abrasives that make "metal particles" completely irrelevant. the reason to clean is so you get braking, not lubrication when the brakes are applied the first time.