Warped rotor pics.

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Not saying you are doing this but father in law had rotors resurfaced and they were chucked on an angle that would have looked something like that and the braking was awful after he installed them.
 
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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.


Exactly.

For 50 years, the solution to *any* brake pulsation was: Turn the rotors! For some people, it still is.

The reality isn't that simple. Excessive lateral runout can be caused by thickness variation, warping, or even stacked tolerances. Yeah, pad deposits can cause a pulsation too. Knowing how to identify and the proper correction for each situation is the difference between Bob's Corner Brake Shoppe, where he resurfaces every rotor (even new replacement ones), and a decent technician who can read a dial indicator.
 
I think the majority of times people says my brake rotors are warped and its causing a shuttering when braking its pad deposits. But I agree that rotors can still warp.
 
Originally Posted by spk2000
Not saying you are doing this but father in law had rotors resurfaced and they were chucked on an angle that would have looked something like that and the braking was awful after he installed them.

The first one turned fine. No wobble. this one looked like that so I turned it 180* and moved the adapters. Still cut in the same places so I cut it till it was smooth. Customer brought the truck in because it had a bad brake pulsation. It stops great now.
 
Originally Posted by Chris142
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.


I don't know why, but on every Dodge product I've had (that's been quite a few) the rotors have warped. 1990 Ramcharger, early 90's Plymouth Acclaim, 2004 Dodge Ram 1500, 4 Dodge Chargers, and a 2015 Jeep Cherokee. Every, single, one. After rotor replacement, no problems. No problems with other makes I've owned either.
 
Originally Posted by MrHorspwer
Quote
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.


Exactly.

For 50 years, the solution to *any* brake pulsation was: Turn the rotors! For some people, it still is.

The reality isn't that simple. Excessive lateral runout can be caused by thickness variation, warping, or even stacked tolerances. Yeah, pad deposits can cause a pulsation too. Knowing how to identify and the proper correction for each situation is the difference between Bob's Corner Brake Shoppe, where he resurfaces every rotor (even new replacement ones), and a decent technician who can read a dial indicator.


+1 That about covers it.
 
When i think of warped, to me that means "wavy". That rotor looks bent ! Like draw a line from 8 o'clock to 2 o'clock and bend the top portion of the rotor away from you along that line.
 
While a lot of it is brake material on the rotor, rotors can warp. A dozen+ years ago, I had a front wheel bearing suddenly fail on my Aerostar. I was a good 25 miles from my home, so I coasted into a repair shop where I knew the independent owner who fixes all makes and models. I knew that the factory rotors had a lot of miles on them, so after he measured them (and I watched) we both agreed that it needed new rotors. When he ordered them, he couldn't figure out why the parts book showed a separate number for the left and the right rotors and I told him that the Aerostar rotors have a directional internal fin to aid in cooling and he told me that he learned something that day.
Fast forward to a week later and the Aerostar's steering wheel shook violently when braking. I attempted to take the first wheel off and I couldn't do it with a 25-inch breaker bar. I had to put a cheater bar on them to take both wheels off. The "mechanic" had tightened the lug nuts on both front wheels so tight that I couldn't get them off without the cheater bar. (Hey, I'm 6'6" and 250 lbs. I'm no weakling)
Putting a dial indicator on the rotors showed that they were extremely warped. I put them on the lathe, trued them up and all was well after that. I attribute the warpage to new rotors and the fact that the lugs nuts were on extremely tight.
I never talked to him about it. I'm sure he put the lug nuts on with an impact wrench that was turned way up.
 
I had bad shudder on my Toyota Camry, runout on left front rotor was .001", not +/- .001", just .001", but the glazed half versus non-glazed half was obvious.

The jamoke that wrote the Stoptech article was also the brake consultant on the Ford GT program.

Yes warped rotors really happen. Stuck caliper overheating, as mentioned. Or, put a flat rotor on a car crooked, run it until it shudders, then put it correctly on a brake lathe and you'll cut lots of metal.

But every case of "warped" I've run into has been either a bad install or uneven glazing. I've also never successfully gotten a runout reading from a service writer. Maybe I'm just a jamoke, too. But I know how to use my Starrett indicator.
 
The warped rotors on my Impreza magically disappeared after I re-bedded them. Guess subaru has built-in lathes...
 
Originally Posted by HangFire
I had bad shudder on my Toyota Camry, runout on left front rotor was .001", not +/- .001", just .001", but the glazed half versus non-glazed half was obvious.

The jamoke that wrote the Stoptech article was also the brake consultant on the Ford GT program.

Yes warped rotors really happen. Stuck caliper overheating, as mentioned. Or, put a flat rotor on a car crooked, run it until it shudders, then put it correctly on a brake lathe and you'll cut lots of metal.

But every case of "warped" I've run into has been either a bad install or uneven glazing. I've also never successfully gotten a runout reading from a service writer. Maybe I'm just a jamoke, too. But I know how to use my Starrett indicator.


While deposits can certainly cause pulsation the statement "rotors do not warp" is an incorrect statement regardless of who wrote it and what program they have or claimed to have been involved in.
I know how to use all my measuring tools inc the dial indicator, so what does that get me a gold star? LOL
 
Originally Posted by bobdoo
The warped rotors on my Impreza magically disappeared after I re-bedded them. Guess subaru has built-in lathes...

You did have pad deposits.
 
Originally Posted by zorobabel
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.

Brake deposits can happen with modern NAO "ceramic" pads with cohesive friction that the Japanese(Akebono/Advics/Nisshinbo[NBK]), it's been reported with Akebono ProACTs.

I'm a believer in warped metal, most rotors are coming from China these days. Cast iron is brittle and some rotors don't need much to get bent out of shape.
 
This debate about whether rotors warp or not is funny.

Turn about 100 rotors on any brake lathe you want and see what you think.
 
I don't see any debate here , about the rotors anyway. People quoting the real racing brake expert engineer's paper and trying to make it say something it doesn't, then others using that as a straw man, I do see.

Re-read the stoptech article carefully and see if there's really anything to disagree with.

I'll tell you something that's no myth, service writers blaming owners for warping rotors, while having no runout measurements to base it on. Caught in the act, several times, by me. Proven wrong, with my instruments. So yeah I get a gold star, not a participation trophy.
 
Originally Posted by Chris142
Originally Posted by bobdoo
The warped rotors on my Impreza magically disappeared after I re-bedded them. Guess subaru has built-in lathes...

You did have pad deposits.


That was the point of my post... Is this when I'm supposed to do the /s thing?
 
With so many aftermarket choices now days
And the cost of turning old rotors
It's not worth the hassle
I buy quality rotors and pads and replace and throw the old junk away
 
Originally Posted by HangFire
I don't see any debate here , about the rotors anyway. People quoting the real racing brake expert engineer's paper and trying to make it say something it doesn't, then others using that as a straw man, I do see.

Re-read the stoptech article carefully and see if there's really anything to disagree with.

I'll tell you something that's no myth, service writers blaming owners for warping rotors, while having no runout measurements to base it on. Caught in the act, several times, by me. Proven wrong, with my instruments. So yeah I get a gold star, not a participation trophy.


You don't see any debate because you don't have the experience other than what you read on the net. I started in the trade when most cars with disc brakes had no hub mounted rotors they were spindle mounted and included the front wheel bearings in the rotor itself.
You packed the bearings, adjusted the bearings and checked the run out, if it was good you mounted the calipers and pads which were mostly semi metallic. if not you trued them on a brake lathe as it is not possible to shim or index them.

Whenever we got a car with pulsating brakes the rotors were distorted, it could be the pads wore the softer areas of the rotor quicker and cause it but in any case they were no longer true. So I suppose if someone is a armchair engineer you could say distortion is not the same as warping but the end effect is the same.
Floating steel rotors common on motorcycles and carbon racing rotors do not react the same way and rarely have pulsation issues, it appears to be a cast iron issue and high carbon content iron seems to be more resistant to it.
 
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