Warped rotor pics.

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In the past people here have said that rotors don't "warp". That shaking or shuddering during braking is caused by brake pad deposits.

This is on my lathe right now. You can see the spots where the bit is not even touching the rotor. Definitely NOT pad deposits.

The bits are missing the rotor on opposite sides like you would think it would if a rotor was warped.

Thoughts?

IMG_20190521_094057.jpg


IMG_20190521_094114.jpg


IMG_20190521_094106.jpg
 
I have said the same thing many times, my brake lathe doesn't lie. It is not pad deposits its metal.
Edit: That bit of misinformation about pad deposits was written by some jamoke and its been touted as gospel ever since, its crap and anyone that has run a brake lathe knows it.
 
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How old are the rotors? Around here I'd guess around 6 months at most--but you're over there, so those could be six years. Curious if they were bad out of the box. They certainly don't look like they have any grooves on them, so they look lightly used.

Maybe they got dropped a few times?
 
Do you crank down the parking brake, especially after a hot day? Lexus has this issue with the hat warping from too much parking brake pressure clamping down on the first gen GS300. They redesigned the rear rotors & we had to loosen the brake adjustment.
 
Originally Posted by supton
How old are the rotors? Around here I'd guess around 6 months at most--but you're over there, so those could be six years. Curious if they were bad out of the box. They certainly don't look like they have any grooves on them, so they look lightly used.

Maybe they got dropped a few times?

Originals on this 05 ram 1500.
 
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Originally Posted by mehullica
Do you crank down the parking brake, especially after a hot day? Lexus has this issue with the hat warping from too much parking brake pressure clamping down on the first gen GS300. They redesigned the rear rotors & we had to loosen the brake adjustment.

This is on the front brakes. No parking brakes on the front.
 
I don't recall hearing that brake rotors don't warp, obviously they do. What I have heard is that sometimes brake shuddering is due to deposits and not always due to warped rotors. I've stopped the shuddering by just cleaning up the rotors and pads numerous times.

Again, not saying that rotors don't warp. They do.
 
I had a problem for the longest time on my Expedition with front rotors warping. Replaced them with new ones with new pads as well, same problem after a short amount of driving. Ended up replacing the bearing hub to solve the problem (with new pads and rotors again). I had to use a micrometer to troubleshoot the hub being warped.
I theorize that with the warped bearing hub, that the rotors would heat up more on the high side and over time warp the new rotor.
I think the problem may have come from when I got the truck used from Connecticut and the front rotors needed replacing but were rusted on to the hubs. The dealer said they had to heat them up and beat them aggressively to get them off.
 
Originally Posted by Chris142
In the past people here have said that rotors don't "warp".
Thoughts?

Sensationalism started by the stoptech blog with the brake deposits.
I have warped rotors descending mountain passes twice. Another time, a malfunctioning MC managed to warp a rotor and it's replacement before I figured out the cause. Another time a friend warped his rotors descending a mountain pass - I was a passenger.
 
today most rotors are cast in China, even brand names + of course some better than others. i like the UK or USA made EBC rotors said to have higher carbon in them. OE can be crap as well especially newer stuff as quality seems to be getting less as technology progresses
 
Have your lathe adapters been indexed to the brake lathe arbor and faced off to true up the assembly? If not, then you're probably doing more damage than good with that lathe.

Easy enough to check. After "fixing" that rotor on the lathe, measure runout after you install it back on the hub. Let us know what you find.
 
Originally Posted by lbhsbz
Have your lathe adapters been indexed to the brake lathe arbor and faced off to true up the assembly? If not, then you're probably doing more damage than good with that lathe.

Easy enough to check. After "fixing" that rotor on the lathe, measure runout after you install it back on the hub. Let us know what you find.
I knew someone would bring that up!
Did that! After I took those pics I 180'd the rotor. Cut the same spots on my 2nd pass.
 
and...after the rotors went back on the hub...what was the installed runout?

Also, when was the last brake service? Is it possible that someone machined those things 5K miles ago or so and the "warped", so you're undoing previous crappy work?
 
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I am on team warp. Have seen it.

In fact when I did the brakes on the Caprice I used high quality AC/Delco stuff. High quality ha!

I lowered the car at the same time and developed a vibration I couldn't find. Had the alignment done and replaced the sway bar end links.
I lived with it like that for 9 months. Finally I was like "I wonder if the new brakes were warped out of the box?" The vibration was weird. Would do it without applying the brakes
often. Purchased a set of Powerstop rotors with new pads. Bingo!!! Smooth as silk. Checked the runout on the AC/Delco rotors, I forget the number but
they were so far out they caused the vibration I was seeing at around 50 to 60 mph. Crazy!
 
Originally Posted by ls1mike
I am on team warp. Have seen it.

In fact when I did the brakes on the Caprice I used high quality AC/Delco stuff. High quality ha!

I lowered the car at the same time and developed a vibration I couldn't find. Had the alignment done and replaced the sway bar end links.
I lived with it like that for 9 months. Finally I was like "I wonder if the new brakes were warped out of the box?" The vibration was weird. Would do it without applying the brakes
often. Purchased a set of Powerstop rotors with new pads. Bingo!!! Smooth as silk. Checked the runout on the AC/Delco rotors, I forget the number but
they were so far out they caused the vibration I was seeing at around 50 to 60 mph. Crazy!


Those were made wrong, they didn't warp.
 
Originally Posted by lbhsbz
Originally Posted by ls1mike
I am on team warp. Have seen it.

In fact when I did the brakes on the Caprice I used high quality AC/Delco stuff. High quality ha!

I lowered the car at the same time and developed a vibration I couldn't find. Had the alignment done and replaced the sway bar end links.
I lived with it like that for 9 months. Finally I was like "I wonder if the new brakes were warped out of the box?" The vibration was weird. Would do it without applying the brakes
often. Purchased a set of Powerstop rotors with new pads. Bingo!!! Smooth as silk. Checked the runout on the AC/Delco rotors, I forget the number but
they were so far out they caused the vibration I was seeing at around 50 to 60 mph. Crazy!


Those were made wrong, they didn't warp.

I know my, I guess it should have mentioned they got worse the longer they were on there, but you are correct they were manufactured out of round.
 
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