Warped Rotor, daily driver

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RamHemi18

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So my ram 1500 CC is my daily driver. I sold my camper so I rarely tow now. My commute is a lot of stop n go traffic, with that comes the often brake slam when someone cuts me off. Ive noticed some vibration when I go to brake which I am assuming is a warped rotor or stuck guide pins. Last year at about 44K I changed the brake pads to wagner OEX ceramics as well as lubed the guides and slide pins, I did not change the rotors (I was being cheap). I now have 56600 on the truck. I plan on pulling everything apart again and re-lubricating the guides and pins again to see if something is maybe binding. If that doesn't solve the issue I think I will turn to the rotors. I am considering drilled and slotted rotors, my thought is with the constant stopping and heat build up, they should cool better, hopefully preventing warping again, not sure if my thought process is correct or not.
Question 1, since I just put new pads on last year, do I need to put new ones on again with new rotors?
Question 2, I am between a few drilled and slotted kits, would I go wrong with any of these? I know powerstop has a pretty good following here

Any input is greatly appreciated, sorry for the lengthy post
 

OC455

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Brake rotors usually warp from the lug nuts not being torqued right when putting the wheels back on. Heavy stop and go would cause brake fade more than anything.

Have you checked to see if the front hubs/wheel bearings are good?
 
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RamHemi18

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Brake rotors usually warp from the lug nuts not being torqued right when putting the wheels back on. Heavy stop and go would cause brake fade more than anything.

Have you checked to see if the front hubs/wheel bearings are good?
I have not checked the hubs and bearings yet, honestly I didn't even think of that. I will have to jack it up and shake the wheel and see if I notice a wiggle. I do only notice the vibration while braking.
 
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indept

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When you cut or install new rotors sand the pads to remove any grooves fron the old rotor or they could score the new rotors. Lay some sandpaper on a good flat surface and rub the pad on it to assure a good flat surface.
 

Atcer2018

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Not to hijack this thread but does anyone know how to determine if a rotor is warped without any special tools? I recently picked up two Wagner E coated rotors on Amazon warehouse special for less than half price each. They do not appear to have been used. I just want to make sure they are not warped and true before I install them with Wagner OEx pads. I appreciate any advice.
 
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RamHemi18

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When you cut or install new rotors sand the pads to remove any grooves fron the old rotor or they could score the new rotors. Lay some sandpaper on a good flat surface and rub the pad on it to assure a good flat surface.
Good idea, thank you
 

Phirebeard

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Not to hijack this thread but does anyone know how to determine if a rotor is warped without any special tools? I recently picked up two Wagner E coated rotors on Amazon warehouse special for less than half price each. They do not appear to have been used. I just want to make sure they are not warped and true before I install them with Wagner OEx pads. I appreciate any advice.
Your local O'Reilly should have a brake lathe. Not sure if Napa still does that or not. Unless you have a known true rotating assembly that you can put the rotors on, I'm not sure of another way. Checking the runout is what you call it :)
 
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RamHemi18

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Not to hijack this thread but does anyone know how to determine if a rotor is warped without any special tools? I recently picked up two Wagner E coated rotors on Amazon warehouse special for less than half price each. They do not appear to have been used. I just want to make sure they are not warped and true before I install them with Wagner OEx pads. I appreciate any advice.
wouldnt mind knowing this myself
 

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You need a dial indicator. You rotate it and see if the delta is > than the acceptable amount. You would mount the rotor somewhere, where you can freely spin it without it moving side-to-side, you put the dial indicator up to the rotor and watch it as you rotate the rotor.

 

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I think dial indicators should still be pretty cheap at harbor freight tools
Some auto parts places will loan you tools.

If you take your rotors in to be turned just realize they charge close to about the same price as a new set.

Make sure you know your tolerance specs and the counter guy knows how to measure your rotors correctly

They always push for selling you new over turning your old ones
 

JPT

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I never cut rotors. I just replace. Since I do the brakes myself, I save enough that I justify (to myself) replacing the rotors. Maybe if I could cut rotors at home, I would consider it, but by the time I can get to a shop, wait for them to machine the rotors, I could have by brakes all back together and back on the road.
 
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I never cut rotors. I just replace. Since I do the brakes myself, I save enough that I justify (to myself) replacing the rotors. Maybe if I could cut rotors at home, I would consider it, but by the time I can get to a shop, wait for them to machine the rotors, I could have by brakes all back together and back on the road.
Exactly. I replace them myself as well, they're simple enough
 

Atcer2018

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Phirebeard, JPT and Mr. Luck thank you for this information. Being lazy I will first attempt the local parts places and see if they do this service. If not I’ll be hitting Harbor Freight or Amazon for a dial indicator. JPT thank you for the YT link.
 

GsRAM

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Unfortunately, these days, rotors don't have the thickness they used to. Generally, due to that, on a used rotor, until you turn it down to make it true, you wind up close to or below the minimum thickness and even if your above that, they will be thin and prone to warp again.

I just installed all new brakes and rotors on my wife's equinox on Monday. They were the OEM pads/rotors, still plenty of pad left at 63k, but the front or rear rotors have been warped for several years now so I finally changed them out.

Rotors can warp for many reasons, my wheels get torqued with a torque wrench everytime they are off so that was not the cause of the warping, but it can certainly be if all lug nuts are not pulling with even torque.

It can simply be design and vehicle weight. My wife is not hard on brakes, yet they still warped. It's a Chevy design issue. The equinox is heavy and like most GM products is underbraked in my opinion
 

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Rotors cannot really warp. Automotive experts note that rotors are metal discs that are cast under extreme heat conditions. It would take a similar application of heat by the braking system for rotors to bend, which is impossible. Other factors make rotors appear to be warped, so describing such rotors as “warped” is an easy way to explain the problem to vehicle owners.

For brakes to work correctly, brake pads must be applied squarely and evenly against the rotor. But friction can cause some brake pad materials to form residue on certain areas of the rotor, eventually contributing to uneven rotor surface levels. Some spots become thicker, while others may thin out.

Drivers’ own habits, including their braking tendencies, can contribute to uneven rotors. For example, riding the brakes for prolonged periods of time can cause hot brake pads to “paint” the rotors. So constant braking should be avoided.
 
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RamHemi18

RamHemi18

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Rotors cannot really warp. Automotive experts note that rotors are metal discs that are cast under extreme heat conditions. It would take a similar application of heat by the braking system for rotors to bend, which is impossible. Other factors make rotors appear to be warped, so describing such rotors as “warped” is an easy way to explain the problem to vehicle owners.

For brakes to work correctly, brake pads must be applied squarely and evenly against the rotor. But friction can cause some brake pad materials to form residue on certain areas of the rotor, eventually contributing to uneven rotor surface levels. Some spots become thicker, while others may thin out.

Drivers’ own habits, including their braking tendencies, can contribute to uneven rotors. For example, riding the brakes for prolonged periods of time can cause hot brake pads to “paint” the rotors. So constant braking should be avoided.
This right here I find quite interesting " For brakes to work correctly, brake pads must be applied squarely and evenly against the rotor. But friction can cause some brake pad materials to form residue on certain areas of the rotor, eventually contributing to uneven rotor surface levels. Some spots become thicker, while others may thin out. "
When I brake and feel the vibration It feels as if the brake grabs, then grabs more, then grabs less, as if the rotor was warped or the pad is riding over more material then less as if there is an uneven surface.

I don't doubt the way I drive and the stop and go traffic contributed to this. My question was if drilled and slotted rotors would allow more cooling to help prevent this in the future, along with a change in braking habits of course ;)
 

crash68

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The "squarely and evenly against the rotor" is referring to how the caliper pushed the brake pad against the rotor, they're not talking linearly around the rotor.
When I brake and feel the vibration It feels as if the brake grabs, then grabs more, then grabs less, as if the rotor was warped or the pad is riding over more material then less as if there is an uneven surface.

I don't doubt the way I drive and the stop and go traffic contributed to this.
Truthfully going with drilled and slotted rotors are great if you want the look or planning on hitting the road course race track, waste of money for everyday driving.
Most people ride their brakes a lot more than they think. I did work at a place that ran brake dynos, the one engineer there told me it's not so much how hard you apply the brakes that wears them down but any time the pads are touching the rotor. Holding light pressure is worse as it polishes the pad and rotor increasing the braking distances. He does more "brake jobs" in a month than a brake repair shop does all year with the added advantage of knowing the exact braking conditions.
 
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RamHemi18

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The "squarely and evenly against the rotor" is referring to how the caliper pushed the brake pad against the rotor, they're not talking linearly around the rotor.

Truthfully going with drilled and slotted rotors are great if you want the look or planning on hitting the road course race track, waste of money for everyday driving.
Most people ride their brakes a lot more than they think. I did work at a place that ran brake dynos, the one engineer there told me it's not so much how hard you apply the brakes that wears them down but any time the pads are touching the rotor. Holding light pressure is worse as it polishes the pad and rotor increasing the braking distances. He does more "brake jobs" in a month than a brake repair shop does all year with the added advantage of knowing the exact braking conditions.
This does make sense. I do ride my brakes coming to a stop, I believe that is my culprit.
 

EdGs

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What did the OE pads look like when they were changed?

44k is not that many miles, IMO. Were you having issues with them?

It would be nice if you could check the rotors with an indicator or have them checked somewhere.

I had a 2001 Saturn and had bought a new set of tires, and after that I had a flutter that I could feel, mostly when I was up to speed and started to apply the brakes.

Tried rotating the tires, etc., but no dice. My FIL said that the rotors might have been warped when the tires were installed from over-torquing them with an impact gun.

At that time, I had no way to check for warpage, so I bought 2 new rotors (only $39 each, then). Changed them out, and it was like night and day.

RockAuto lists the Wagner rotors for an '18 for $63 each. If these are the correct ones for your truck, that is a decent price, IMO. If it was me, I would buy them.

May your repairs go smoothly.
 

GsRAM

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Rotors cannot really warp. Automotive experts note that rotors are metal discs that are cast under extreme heat conditions. It would take a similar application of heat by the braking system for rotors to bend, which is impossible. Other factors make rotors appear to be warped, so describing such rotors as “warped” is an easy way to explain the problem to vehicle owners.

For brakes to work correctly, brake pads must be applied squarely and evenly against the rotor. But friction can cause some brake pad materials to form residue on certain areas of the rotor, eventually contributing to uneven rotor surface levels. Some spots become thicker, while others may thin out.

Drivers’ own habits, including their braking tendencies, can contribute to uneven rotors. For example, riding the brakes for prolonged periods of time can cause hot brake pads to “paint” the rotors. So constant braking should be avoided.
I just knew someone was going to say this in this thread. Lol. Yes you are correct. But even if the entire disc itself isn't physically altered, if the contact surface itself has been altered, either by residue, changes in material thickness or what have you, in my opinion the surface is "warped", uneven, high or low spotted, or whatever term you choose to utilize to describe it.

When you turn a rotor or a drum on a brake lathe, as I've done many times, as the disc is spinning and the cutting tool is stationary removing material, the surface unevenness (excessive lateral run out, thickness variation or `warped` nature :) ) is very apparant.
 
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