Brake rotor warping - Cryo treatment?

[pcmenten]

I wasn't sure which forum to post this to, so I"m posting it here.

I have a 2014 F150 with 15,000 miles. The brake rotors are warped. I think I know when and how it happened, but it's enough to say that it was under normal operating conditions; a normal load in the truck, driving on the highway at normal speeds.

So my question: will cryogenic treatment help prevent rotor warping? I've done the obligatory google searches, but I'm hoping that some of our more technical types with some experience in this area will offer their wisdom.

The Sunbeam rotors are hell-for-heavy chunks. I'll probably get them treated along with my F150 rotors. As some of you know, I'm mid-way through a V6 swap and I have Mustang II calipers for the front brakes. Stops from high speeds are likely.

 

[Bill Blue]

Paul, have you checked to make sure they are warped or is the diagnosis based on a pulsing brake pedal?

I recently read that rotors seldom warp. The problem is that modern brakes are so over designed the rotors seldom get hot enough to burn off pad residue. Just hot enough to bake the stuff on. The residue has a higher coefficient of friction and of course is thicker than the rotor, leading to the pulsation.

My wifes 1999 ZX2 suffers from almost continuous pedal pulsation. A brake job it is pulsing within 5,000 miles. I have found that several very hard stops in row will ease the problem for a few thousand miles. The car is never driven hard.

Bill

 

[hartmandm]

I used to have rotors go 100k miles or more. Rotors are now intentionally made disposable on new cars. You change them at the same time you change brake pads. They are at the edge of tolerances when brand new. Out of tolerance by the time you need to change the pads. Supposedly for the mass market, one company in China makes all the rotor blanks. There are niche rotor makers, but they are really expensive. So what you are shopping for is who did the final machining.

When new, I bed in the rotors & pads according to instructions to remove the coatings... My experience has been that they typically warp at around 15k miles. I've looked at cryo treatments, but was not able to find them in stock for my vehicles. Worth a try though from what I have read. I've gone the slotted route for some replacements and they seem less prone to warping.

Mike

 

[65beam]

rotors

2014/15K means the problem is the dealers problem, not yours. tell them to install new ones.

 

[greenbean]

I went through a similar problem on a 2010 Dodge mini van. Kept having the dealer replace them until it was out of warranty, 2 - 3 time IIRC. Then bought after market ones and they have 50k on them and are just fine. I sometimes think the dealer was a frustrated as me

 

[Tom H]

I agree with Bill.It's not warping. See this article on "brake rotor warping":

http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

Tom

 

[Bill Blue]

Let's hear it for fig. 4!

I noticed he did not mention ceramic pads. I have them front and rear on the Alpine and they seem to be almost perfect. Stop good hot or cold and I've never had the pulsation problem. However, they tend to groan with heavy application. Drive Barb crazy. Also, they pull a little to one side or the other the first stop or two of the day. So I always try to make sure the first application is an easy one.

Bill

 

[bashby]

I had a brake rotor warp problem with a '81 T-Bird which was under-braked, found that if I used aftermarket pads the rotors warped if I used the softer Ford pads they did not. Disc Brakes Australia (DBA) sells excellent rotors, have had the slotted ones with Hawk HPS pads on both of my past 2-daily drivers with excellent results. I have slotted Wilwood rotors on the front of my SV with Hawk HPS pads too.

 

[RootesRacer]

While it sounds plausible that the issue with pulsation is not warping, if you consider that the material itself is ending up either with differences in hardness as a function of rotation position or inconsistent alloy properties, the problem still sounds to me to be one of materials quality or processing.

I wonder if a quality stainless rotor would net more favorable results than a conventional iron rotor. At least with stainless the alloy is more controllable as will be the carbon content.

Considering the location where most things are made these days (and often a lack of desire to manufacture to specifications), one has to wonder if on shore materials and manufacturing would solve a lot of these problems.

 

[Bill Blue]

I must admit that I have seen a warped rotor. It was in a parts box that came with an Alpine. It was visibly warped, a better description would probably be "cupped". I took it to my local brake guy to get it turned. By the time the cup was gone, it was 3/8" thick. I have no idea what could have caused the problem.

Bill

 

[msmoorenburg]

So my 2cents its the material cast steel vrs cast iron. the cast iron rotors (aka 08 caravan issue i had) it has great stopping power and super quiet but wear out 10-15k miles. When you switch to cast steel you will get the squeel and chatter but you will get 100k miles out of them. Also hard stops and lack of cooling creates holes in rotors. When machining them out on a brake lathe you can see them.It creates holes/lowspots on the rotor and creates the vibs in the foot while braking. Let me have a go at a few rotors and i'll show you the low spots with a pic

 

[msmoorenburg]

here is a cast iron rotor and you can see where i machined the lip off before i made a first pass. this one was not warped



saving a Alpine rotor



A Alpine rotor that has a low spot from rust (holes appear like this)