Another Brake Rotor Problem Question...

[mcn6]

I have an 03 f-350 4X4 That I bought new. I recently replaced the original OEM front brakes with Power Slots and hawk LTS pads (.001" installed run out left and .002" run out right). Everything felt good for a week or so until I heated things up coming down a 5% grade, look out! What started as a very small vibration soon turned into Big vibration to the point I felt it was not safe. I finally get to the bottom and let things cool back down and everything is good to go again with no vibrations just like before.
This has now happened several times on grades and I can also make it happen by riding the brakes for 60 seconds or so to heat things up. I am getting no pulsation through the brake pedal either, just vibration through the steering column, steering wheel and floor board and only after using the brakes for something more than running around town stopping at stop signs.
Power Slot Tech support has been about worthless... They have now blamed it on everything except their rotors, finally settling on some material transfer layer issue because I didn't "brake the pads in properly"? I have had the front wheels off the vehicle 5 times now, I have indexed and indicated the installed rotors as many times, I have indicated the axle flanges, I have torqued and re-torqued lug nuts, etc.
Sorry for the long story, but does anybody have experience with this? Any suggestions or questions?? FMTRVT maybe??? I just want brakes that work and I am tired of jacking this thing up and working on it...

[Frozen Rotors]

Originally Posted by mcn6

I have an 03 f-350 4X4 That I bought new. I recently replaced the original OEM front brakes with Power Slots and hawk LTS pads (.001" installed run out left and .002" run out right). Everything felt good for a week or so until I heated things up coming down a 5% grade, look out! What started as a very small vibration soon turned into Big vibration to the point I felt it was not safe. I finally get to the bottom and let things cool back down and everything is good to go again with no vibrations just like before.
This has now happened several times on grades and I can also make it happen by riding the brakes for 60 seconds or so to heat things up. I am getting no pulsation through the brake pedal either, just vibration through the steering column, steering wheel and floor board and only after using the brakes for something more than running around town stopping at stop signs.


Power Slot Tech support has been about worthless... They have now blamed it on everything except their rotors, finally settling on some material transfer layer issue because I didn't "brake the pads in properly"? I have had the front wheels off the vehicle 5 times now, I have indexed and indicated the installed rotors as many times, I have indicated the axle flanges, I have torqued and re-torqued lug nuts, etc.
Sorry for the long story, but does anybody have experience with this? Any suggestions or questions?? FMTRVT maybe??? I just want brakes that work and I am tired of jacking this thing up and working on it...

mcn6,

Uneven pad transfer can happen but the Hawk LTS brake pads don't typically have this issue. Do the brake rotors look discolored, blotchy, or streaked?

[Early Cuyler]

If you have carefully torqued your wheels on installation, all thats left is you have improperly heat-treated rotors which is very common and nothing will fix them but exchange. When you remove mass from brake rotors so that they look cool as in drilled or slotted, you just set it up for failure. Cracking and warping are the result. You need more mass in your friction heat exchange mechanism not less.Youre not driving a Trans-Am car or Seca bike.Use a well known brand rotor like Wagner SSBC Raybestos or maybe even Frozen Rotors,I hear good things about them,tho I have never used them.Not even new Corvettes use these wanker rotors, and thats all about looking cool.

[mcn6]

Thank you for the comments.
There is absolutely nothing unusual with the appearance of these rotors. In fact, there are still quite a few of the grinding marks from the factory still clearly visible.
I am not buying Power Slot's "material transfer" thing either... Thus my posting the question here. If I screwed something up then every vehicle with a new set of front brakes would/should have the issue also. I mean really, you have to stop at stop lights and crosswalks and stuff whether you have new brakes or not!
Trans-Am or Corvette, LOL! I still have the original steel wheels and hub caps on this thing... I would probably get more "cool" with a mini van.

[FMTRVT]

If your runouts were excessive it would take a few 10k miles for the resulting pulsation. Runout would have to be in the 0.008 to 0.010" range to have that issue right out of the box. For me right side is a little high, but with these pads will work. Great job in taking the effort to do that.

There are two things I would recommend. One is to loosen then re-torque the front wheels. Cryo or not, going through a heat cycle can stress relieve rotors so they actually result in a wavy pattern after heat.

I would suspect the rear rotors, although you should have seen some of this before the front brake change. I've got a whole group of people that have replaced front rotors several times (including dealerships) when it was the rear rotors all along (Chusckster57 has a clients story for example).

Since it is easy for you to repeat the issue what I would suggest will require some open road and a set of hose clamp pliers. Get out to open, very low traffic road and with the brakes moderately cool clamp off the brake hose drop from the frame to the axle on the drivers side. Then go play with you method of developing the issue and see if front brakes only cause the problem. If you have a heat gun, taking rear rotor temperatures after clamping the hose and then after doing this procedure can confirm if the rear brakes were doing any work during this test. You don't want them to.

Keep in mind that this vehicle does about 45% of the braking off the rear brakes, therefore the need not to be in traffic.

Despite all the "break-in" procedures requested by pad manufacturers, it really takes a fair amount of miles and brake events to fully bed in a new set of pads and rotors. During this time if the rear brakes were not changed they will be doing a higher percentage of the braking (maybe 65% on this vehicle). This is enough of a change to make what could have been a hard to feel problem into a major one. At least until the front pads and rotors are fully burnished. The fact that you can still see the original grinding marks in the front rotors reinforces to me this is what is happening.

[mcn6]

Thanks FMTRVT, I was hoping you would comment. I only indexed these rotors after having problems with the initial installation and test drive. They were noticably worse than they are now before indexing.

Here is what I did this afternoon... Pinched the rear brake line as you suggested and it is definitely the new rotors up front, acted just like usual without any rear brakes. Next I removed the hose pincher and went for another test drive using just the emergency brake to heat the rears up and after a while I noticed a very, very mild vibration (if this was as bad as it got I would be happy...) Next I let things completely cool down up front, loosened and re-torqued the the front lugs and surprisingly, this did help a little, but it is still the same old stuff... I actually noticed the engine hood deflecting in the middle from the shaking along with the usual steering column and steering wheel shake. It must have been there, but I had not noticed it before?

Short story from today even shorter: The rear rotors may be contributing to the shaking slightly, but it was a very different feel coming from the rear and, at most, it is very, very minor. It is defenitely the front rotors! And it is the same old issue, although slightly better after re-torquing the fronts, still not even close to acceptable though. And I am still not feeling any pulsating through the brake pedal.

BTW, the PowerSlots up front don't even have 500 miles on them and a decent part of that doing test runs...

Isolating the fronts from the rears helps settle this a little in my own mind, you are the first to suggest it.

Thank you for your help.

[FMTRVT]

I was biting my tongue while writing that hoping you were not going to find a front issue and have to go through that hassle.

BTW, you did a very good job on your own in diagnosing the issue. It's always a lot of work.

[mcn6]

I am not looking forward to it either...

It would be a huge understatement to say that I am very unhappy with PowerSlot and their Tech Support right now.

Thank you again for your help.

[Blue12]

After getting 60,000 mi on the original rotors and pads (and, with NO vibration) on our ’04 Expedition, doing a fair amount of trailer towing, I allowed the Ford dealer to install Motorcraft pads and rotors—big mistake. Vibration by 10,000 mi; turn the rotors; vibration again by another 10,000 mi. I then had an independent shop install Power Slots and hawk LTS pads. They were just fine for 15,000 mi, but I now have a slight vibration—nothing I can’t live with. I wonder if they are just not up to towing and/or big truck demands. When the 2012 F-350 needs brakes the first trial will be Ford OEM Blue Box (NO Motorcraft) parts, regardless of cost.

[FMTRVT]

I'm not sure that blue-box rotors are still available for the '99-04 MYs.

Despite what seems to be a common belief amongst consumers, in my 30 years of working in the brake industry in most instances you will not find a better made rotor in the aftermarket compared to OE. Some low cost platforms there is a benefit, but that's not the SD platform.

Yeah the aftermarket will claim this and that, all not substantiated.

Powerslot was using OE TRW rotors at the start, now I'm not sure if TRW has stopped making them for Ford. When mcm6 removes his rotors it would be interesting to see if the hat section has the TRW logo cast in place and they are the "post' vane, not straight vane construction.

Ford had put demands on the Federal-Mogul rotor production for the "MotorCraft" red box items, but it's still not am OE level product. For aftermarket, they are better then others.

The biggest factor in preventing pulsation that an installer can do is to check that the installed runout is under 0.0015". If the rotor pulses immediately, then it's got non-parallel rubbing surfaces out of the box. If it pulses later on after good installed runout, then it had casting issues or was not stress relieved.

[mcn6]

I will probably be taking them back off in a few days, I don't remember seeing any manufacturer marks on them, but I will take a better look this next time and report back.

[FMTRVT]

It will be in the center section. Here are views of the '99-04 and '05 and up front rotors showing the IDs and vane constructions. The '99-04 are the lower rotor with the post style cooling vane design.

[mcn6]

Thanks for the pics, I was wondering what "post" style vains were...
These powerSlots are definitely not post vains. I remember from the initial install and subsequent R&R's that the vains are curved and that the rotors were marked right and left.

Might you have any tips or tricks to speed up the indexing process? I had never indexed rotors prior to this so I simply installed the rotors using an air impact gun with large flat washers between the rotor and lug nuts (no wheel). I then indicated the rotor for run out, disassembled and repeated... Since I saw no way to hold the assembly to torque to 165 ft-lb with a decent torque wrench, I just relied on the torque the gun was putting out at a steady air volume and psi (apx. 120 ft-lb).

At any rate, the above method worked... However, I was curious if there was a quicker and/or more accurate way of doing it??

I should be able to check for manufacturer pretty soon after Thanksgiving.

[FMTRVT]

For indexing you don't have to torque them down the full wheel install value. We had good, very repeatable results torquing down to 60 lb-ft and using every other lug only. If we were under the 0.0015" spec we left the rotor there. Typically we never had to rotate the rotor on the hub to meet the spec with OE rotors.

[mcn6]

I just finished replacing the POS PowerSlots that were heat distorting with NAPA's finest Chinese made rotors and premium brake pads... And they work PERFECT! I am now totally happy with my truck brakes. I put about 20 miles on the NAPA stuff just cruising around town stopping at stop lights and whatever. Then I heated the front rotors up similar to what I had been doing with the PowerSlots and no problemo... Nice smooth brakes no matter how hot the rotors got, within reason of course.

There were no manufacturer marks on the PowerSlot POS's other than a small round paper sticker for left and right, the letters CRYO in white ink and A0514 cast into the left rotor and M081D cast into the right one.

I installed NAPA rotors and not OEM Ford rotors because the guy behind the parts counter was not very sympathetic to my plightWhereas the parts guy at NAPA said I could return the parts if there was a problem "

on edit:
I just edited the above because after taking a closer look there are in fact minimum rotor thickness and other numbers stamped into the very outside diameter of the PowerSlots similar to the OE and Napa rotors. Just had to clean some brake dust off to see it is all... Still did not see a manufacturer though.