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I just replaced rotors/pads/calipers with cheapest advance auto parts had to offer. I'm very happy with the results, I even go near my brakes and it stops quickly. Probably the best feel I've ever had from any car/truck. Total cost was under $500 including calipers.
When I bought my Ex last summer, the rotors were warped really bad and would violently shake the whole front end when slowing from any speed. I didn't have time to go through it all before leaving on a 7 day camping trip out of state. Took it to my local mechanic (whom I trust) and had him replace all the fluids as well as a full brake replacement. Pads front/rear and new rotors up front ran me around $450 installed and all seemed well. He doesn't believe in turning rotors on a rig this big (8-10in lift and 35s at the time), so new rotors were installed from Napa. A year and 11k later, its starting to get the front end shake again. I'll have the rotors turned by someone else, but if they start warping again next summer, I'll look into having the calipers replaced and install some vented rotors. My camp trailers seem to get bigger every few years, so I need to get this problem resolved.
Took it to my local mechanic (whom I trust) and had him replace all the fluids as well as a full brake replacement. Pads front/rear and new rotors up front ran me around $450 installed and all seemed well. He doesn't believe in turning rotors on a rig this big (8-10in lift and 35s at the time), so new rotors were installed from Napa. A year and 11k later, its starting to get the front end shake again. I'll have the rotors turned by someone else, but if they start warping again next summer, I'll look into having the calipers replaced and install some vented rotors. My camp trailers seem to get bigger every few years, so I need to get this problem resolved.
Your mechanic who you claim to trust but don’t want to follow his advise is correct in not turning the rotors unless he has the ability to do them on the vehicle.
your current rotors are vented as nobody makes a non-vented solid rotor for the Ex-f250 platform.
your trailer brakes should be handeling the stopping chores of the trailer completely independent of your Ex braking, ( in other words towing should not be killing your Ex brakes ) sounds like you either need a better controller and have it adjusted correctly or your trailer brakes themself are in need of repair.
What I meant to say was that I intended to install some drilled/slotted rotors in the future. In the past year and 11k miles, I've only towed my camp trailer on one trip totaling about 900mi. There were a couple of local trips with the boat, but that's about it. In my professional opinion, they should have lasted much longer.
I've had my X for 4 years now and with previously towing a 37' camper I went through brake pads on a regular basis even with a trailer brake equipped. Last year I replaced rotors, pads, calipers all the way around with the powerstop kit and not only is my braking awesome but I haven't had to do pads this year. I registered just to tell you about this brake kit, it's that good. Ordered from summit and it was delivered to my hour within a few days.
Drilled and slotted in of itself is not going to add any longevity and in fact many drilled rotors fail quicker then non drilled simply because they crack where the hole is drilled. On the Ex the drilled and slotted rotor is just for show as brake pad degas is not a huge concern like it is on race cars that run organic brake compounds, you should be running a semi metali pad and they do not degas like an organic pad.
and yes your brakes should last longer then 11k.
For reference the stock rotors and pads often last 70k miles. People are quick to want a diffrent rotor but in my professional opinion few companies can match the quality of the motorcraft rotor. Your case being a perfect example.
When I bought my Ex last summer, the rotors were warped really bad and would violently shake the whole front end when slowing from any speed. I didn't have time to go through it all before leaving on a 7 day camping trip out of state. Took it to my local mechanic (whom I trust) and had him replace all the fluids as well as a full brake replacement. Pads front/rear and new rotors up front ran me around $450 installed and all seemed well. He doesn't believe in turning rotors on a rig this big (8-10in lift and 35s at the time), so new rotors were installed from Napa. A year and 11k later, its starting to get the front end shake again. I'll have the rotors turned by someone else, but if they start warping again next summer, I'll look into having the calipers replaced and install some vented rotors. My camp trailers seem to get bigger every few years, so I need to get this problem resolved.
You're chasing the same problem I had back when I first bought my Ex. Cryo treated rotors and Hawk LTS pads have always been the best bet for me in braking for the Ex. Just recently I tried a NAPA rotor just to see if the problem came back and it did. Hot spotting/black spotting cementite followed and I quickly dropped those boat anchors and put on another set of cryo treated rotors.
25 years testing brakes, a few thousand tests (like 10,000), and using measuring equipment that cost what a new King Ranch costs today never showed a rotor heat warp. Showed them wear unevenly, especially when installed with a higher runout then spec'd. There's a lot of new aftermarket rotors out there that don't meet runout spec and won't come in with indexing.
Rotors can be turned and work fine. They need to be turned on the vehicle with an on-car lathe to maintain the proper runout. Often you can beat the OE spec. Bench turned rotors, not so much. And if they already have developed cementite they can never be corrected. Learn that lesson enough the hard way and you won't bother turning rotors ever again. It comes back to bite in 5-10k miles and makes you think they heat warped. They didn't. The hardened area doesn't wear the same so back to the disc thickness variation just like a high runout rotor.
OE on the F350. And I mean OE, not Motorcraft. The post vane K-H/TRW rotors that were assembly line for '03. TRW went to straight vane on the '05+. When we shut down the facility I had to get rid of stock not being transfered to MI so I grabbed enough front and rear rotors to last me through 500k. For our Lincoln LS I only grabbed one set (we were the friction supplier on that too) so the second replacement set was Motorcraft. Those all measured in on runout.
The OE original designs are typically well made for Ford. The Motorcraft are probably next in line due to Ford insisting on Federal-Mogul meeting the OE specs for machining tolerance and some checks on casting consistency. But the very well known brands get there too with their premium priced rotors.
In the aftermarket you can see a drop off in quality. The machining for runout and surface finish may not be as tightly controlled. You can have a little more vane core shift which can lead to the parting line seam earlier in this thread, but more troublesome is a variation in the outer rubbing disc thickness which can lead to uneven temps around the rotor. Often that leads to hard spots, but so does a poor mix of the alloy or a temperature variation during casting. And no one in the aftermarket field tries to match the OE cooling vane design, they just go with whatever casting patterns they already have.
But the biggest factor in good running rotors is the installed runout, keeping that as low as possible. So the best machining and casting usually follows price.
The cryo rotors did improve on the runout causing pulsation issue, typically for two reasons. The guys doing the cryo work usually bought well machined rotors, but the cryo process also develops a wear resistant rotor, lower where typical rotors are made to. Its also why you mostly see cryo rotors sold with a higher friction pad. The decrease in wear resistance reduces the coefficient of friction to a certain extent, so you need high mu pads to keep or improve the pedal effort during the colder brake applications. And the surface wears less so it's not effected as much by the runout.
It's a Column A vs Column B event. Standard rotors installed at a low runout with the proper rotor abrasion formulation keeps the rotor true without developing disc thickness variation. Cryo rotors allow for more runout as they have a lower wear rate, but you need to kick up the friction. We tried them with OE material on both the dyno and vehicle and saw the same result.
Rotors are not rocket science. They just need to be well made and installed correctly. It took the brake industry and the vehicle manufacturers a few million dollars to figure that out. The service industry propagated the heat warp (especially after turning) since the 60's because no one spent the time and money to fully understand it until starting in the late 1990's. And then the automakers still didn't fully embrace the concept. Ford mostly did around 2001-2003, but others were still 5 years behind.
Great info Jack, thank you!
One question about the cementite you mentioned, does that transfer into the rotor from hard braking and then sitting still with the brakes applied as they cool down some? I always try to leave enough room to allow me to creep slowly forward after a stop to keep from having the hot pads sitting still hard against the hot rotor. I do see good brake like and haven't had the pulsing ("warped" high spot) issues at all.
Drilled or slotted snake oil aside, I believe powerstop must use decent cores as I have had really good long term results on the last 6 sets I have installed for myself and others. Anecdotal for sure, but the price has me using them more often. I also do as Tom and creep at stops as I imagine the hot pads clamping a hot disc in one spot could be an issue. Videos of rotor meltdowns on YouTube confirm that it makes some differnced in temp
I made some corrections to the post last night. Me waking up at 1am because of my sinus issues doesn't necessarily get the best writing. And this morning I still have a raging headache.
I'm a friction material guy, not a metallurgist or rotor guy. I just had to work with the issue for 30 years. And I don't have the enthusiasm about taking brakes as I used to.
The issue of hard spotting is way more complex then clamping on one spot or driving through puddles. And many of the "rotor guys" I know believe it to be a baked in problem caused at the casting plant, not allowing the rotors to cool properly in the molds to have a better homogeneous alloy. So again, back to price.
Rather then me babbling on I'll post some links that you'll probably never read.
This person did a good overview of the brakes in general and covers many of the issues. The reference list is exceptional.
An OK paper relating to cryo rotors. Not conforming to what we saw internally on the dyno and vehicle tests. BUT, the term "cryo" covers a wide range of processes.
Jack,
again thank you for the tech, bookmarked all for through study but I just scanned the TRW paper. In 10 minutes it answered ( or at least gave a clue ) to several question I’ve had.
Hope you feel better soon, those sinus headaches suck.
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