Bent rotors, what's causing it? - Focaljet

**SanDiegoBMX** · 01-10-2002, 11:23 AM

I hit a curb going 30 or so mph around 6 months ago. The impact was enough to bend a rim and a control arm. I didn't go through my insurance company because the cost of fixing it was lower than my deductible. A month or two later, my rotor became severely warped. I spent 80 bucks, bought a new one and put it on myself. Problem solved for a good 3000 miles, then it happened again. I took my car to a dealership, got it covered under warranty (hook-up), and they replaced both front rotors and both pads. 4000 miles later, they’re bent again. Take it back, they do the same thing, and now not even 2000 miles I can feel it happening again. So, my question is: What else could be causing the rotors to consistently bend? Calipers? Frame? Axle? I don't know too much about cars, but I do know that this is no fun. Any ideas/answers would be greatly appreciated.

Moderator, I couldn't decide between the wheel/brakes forum and this one. Feel free to move it to whichever forum you feel this post belongs in.

-Ryan

**drivefaster** · 01-10-2002, 08:53 PM

Just so you feel better, 80,000 miles and never a warped rotor! If they were going to, they would here in the hills of southwestern PA.
I had a problem with the hub that holds the wheel lugs. The hub fits into the wheel bearing, and the driveshaft fits into the hub. The inside of the wheel bearing actually has two sets of races and ball bearings. When I replaced the right side wheel bearing, everything seemed to be OK for about 20,000 miles. Then it started vibrating and I wasn't sure why, was thinking it was the ball joint or strut pivot but they were OK.
Just before Christmas I had to put new brake pads on. The driver's side went very well. Then when I jacked up the passenger side, the wheel was very loose and wobbled when I moved it. Not good!!

Determined that it was the wheel bearing and luckily had an extra one that I bought just in case. As I got into it more, I found that the wheel nut was loose, problem #1. When I got the hub out of the bearing, the inside half of the hub surface was worn down as if the inside bearing race was locked and it was wearing against the hub, problem #2.
The bearing was ruined and not having a new hub laying around, I had to put it back together with the old one. It's OK so far, but I'll probably need a new hub and bearing soon.

The point is, I think the wheel nut loosened causing the hub to move in and out and wearing it down. The vibration and grinding that I felt, was like what you'd get with a warped rotor or pads that are worn down.
If you have a continuing problem, make sure that the rotors are in fact warped by measuring the runout with a dial indicator. Don't assume that the techs are doing this at the dealership. Also check the torque on the nut to make sure it's tight.

Hope my experiences are helpful!!!

**[\]iteshift** · 01-10-2002, 09:04 PM

Same thing hapened to me. I have 9000 miles on the car and its just my back right rotor. Warped as hell. Breaking at high speeds feels like an earthquake. Taking it in tomorrow. Do they have to special order that part? Howlong should it take the dealership?

**wmudavey** · 01-10-2002, 09:45 PM

dude u have advance trac?

**wmudavey** · 01-11-2002, 12:05 AM

I did the same thing. REALLY pissed me off cause the dealer didn't catch it. So I got new rotors...but they suck. I am so pissed. I got new ones again. I am now on my third set. They just replaced the rotors this past time and not the pads. They shake like crazy. I don't know if they overtorqued the wheel or what. The rotors are too small for my application anyways. I have traction control and in the snow and ice they heat up like a frying pan. This along with cold weather can really ruin them. I don't know if anything else is damaged but it is making me nuts!!!!!!!!

**2001 ZTS** · 01-11-2002, 12:23 AM

I don't know how you drive your car and how hard you use your brakes but what can happen, apparantly, is after you come to a hard stop your discs are very hot. If you keep your foot on the brakes the pads will rest on the same point on the disc. The disc itself will cool at a different rate than the portion of the disc covered by the pads. This could cause warpagedue to uneven cooling.

Just repeateing what I've heard elsewhere. Seems to me to be an extreme case. Maybe someone else can comment.

**SanDiegoBMX** · 01-11-2002, 12:49 AM

ZTS, that sounds good in theory and it may help explain my problem if it were occuring out of the blue. But, my guess is that all my problems come back to that faithful night between the curb and I [img]images/icons/smile.gif[/img] .

wmud, I feel ya.

**noresull** · 01-12-2002, 01:34 PM

I doubt anything in the front end has warped the rotors. I have only seen rotors warp due to wear, improper/uneven torque on the wheels, or bad driving style. I would really suggest analyzing your driving style and make sure that when ever the wheels are removed they are torqued evenly before complaining to Ford again.

The only time I've seen rotors bend or break due to an accident, it was only at the time of the accident. I have never seen rotor issues once they get replaced after an accident.

**SanDiegoBMX** · 01-13-2002, 12:45 AM

niteshift, a day... maybe two.

wmud, nope.

Bump bump bump. I'd really like to put on the fascia that I know what I'm talking about when I go into the dealer next time so they don't just say 'we replaced the rotors, so you won't have that problem again' ...for the third time. Por favor, can someone just name of possible things that may cause rotors to warp so quickly (as in my case)?

-Ryan

**SanDiegoBMX** · 01-13-2002, 02:31 PM

What exactly is bad driving style? I drive like any other person. Any un-even torque issues would be at the fault of the dealership that last replaced my rotors... I haven't touched the wheels since.

-Ryan

**Uriah** · 01-15-2002, 05:38 AM

I re-torque my lugs after any one takes my wheels off and most often I find them way over torqued and uneven. Many people get carried away with air-tools. It is my understanding that even and correct torque on the lugs is especially critcal on 4-lug wheels with modern thin rotors. It does not take long and makes life easier than if I yelled and screamed at my dealer and tried to re-educate all their techs. I think seeing me whip out the torque wrench in their lot has gotten their attention though, as the last couple of times it has come out pretty much right on.

[ 01-15-2002: Message edited by: Uriah ]

**Uriah** · 01-15-2002, 08:58 PM

I think the manual quotes around 84 but I'm more comfortable around 95

**[\]iteshift** · 01-16-2002, 12:36 AM

so exactly how much torque should I give when putting my tires back on?

**MichaelXi** · 01-16-2002, 01:01 AM

UMMMMmmmmm, Nobody has yet mentioned how rotors can warp if they get wet(ie. car-wash) while hot....
[img]images/icons/smile.gif[/img]

**apex** · 01-16-2002, 06:27 AM

I just had my rotors replaced at 29,000 miles. I had noted to the dealer that there were deep grooves in the rotor about the width of the pad. He sai this was 'normal'. I told him that I have rotors on my other car with many time that milage that didn't look that bad. Well now the brakes started to pulsate and he sai the rotors are too thin to machine and they replaced them. My wife says the car is a lot quieter. Maybe drivefaaster stumbled on something with the front hub nut being loose. Possible defect/recall? The dealer spent four woking days on the car. Hmmmmmmmmmm.

**MichaelXi** · 01-19-2002, 01:34 PM

UMMMMMM, have you pondered my idea???
Any Car-Washing, w/ Hot brakes???
Other 'Jetters have done it.
[img]images/icons/smile.gif[/img]

**SanDiegoBMX** · 01-20-2002, 12:41 AM

Bringing this back to the top. So what I'm getting here that my rotors have consistently warped due to over-torque? That just doesn't sound right. I hit a curb, the rotor problem started after the fact. My driving style hasn't changed from before to after the wreck and I'm assuming that ford is competent enough to put the correct amount of torque on my wheels at least 1 out of the 3 or 4 times they've put my wheels on.

**SanDiegoBMX** · 03-05-2002, 12:34 AM

Bringing this back from the dead.

I suppose things are going well. My rotors are still slightly warped, but it hasn't really progressed at the normal pace. I've made a conscious effort to lay off the breaks after coming to a full stop by a) putting it in neutral and pulling the parking break (gives my f'ed knees a good power nap, as well) or b) lightly applying the break for a short while then letting off (allowing the rotor to rotate a bit) and then applying the break again. I suppose my question now is about aftermarket rotors (slotted)... if my so-called thin rotors are warping, are aftermarket rotors stronger; i.e. less prone to warping?

Also, where's a good, cheap place to pick up a torque wrench?

Thanks.

Edit: Michael, when I do wash my car (sadly, not very often) I head straight from work about a mile away to do the deed. But, I suppose it is a possibility. I'll take that into consideration as well.

-Ryan

[ 03-04-2002: Message edited by: SanDiegoBMX ]

**MichaelXi** · 03-05-2002, 12:41 AM

ANY rotors CAN warp. The most common way to warp them is to rapidly cool a HOT rotor. (ie. Car Wash)
[img]images/icons/smile.gif[/img]

**Blink_32** · 03-05-2002, 12:46 AM

<blockquote>quote:<hr>Originally posted by SanDiegoBMX:
Also, where's a good, cheap place to pick up a torque wrench? <hr></blockquote>

If you find a "cheap" torque wrench, don't buy it! Unless there is a sale on a brand name wrench, your just gonna be throwing your $$$ away. At best you would get a few good readings out of it before it turned to crap. Bad thing is you would never know it. See if you can borrow or rent one locally. SEARS carries all Craftsman line of torque wrenches.

**James** · 03-05-2002, 08:53 AM

If you can, stay in the service bay and watch them install the new rotors. When it comes time to zip the wheels back on, be sure that they do not just go in a circle. THey need to make kind of an hour glass figure. And make sure they set the torque at no more that 100 lbs.

**fruitport_focus** · 03-05-2002, 10:13 PM

<blockquote>quote:<hr>Originally posted by James:
If you can, stay in the service bay and watch them install the new rotors. When it comes time to zip the wheels back on, be sure that they do not just go in a circle. THey need to make kind of an hour glass figure. And make sure they set the torque at no more that 100 lbs.<hr></blockquote>

When I had my ZX3 in for the wheel brg recall, I told the tech to torque my Konigs to 94lb/ft. Some cars it is critical to torque wheels or warpage can occur. But SDBMX it sounds like you may have undiscovered damage yet. Things to check would be pad wear(is it even), rotor runout(before rotor is replaced), and all other frt end components-hubs, wheel brgs, axle stubs, calipers(for sticking). Just a thought.
[img]images/icons/smile.gif[/img]

**Shiva Chaos** · 03-06-2002, 01:12 PM

<blockquote>quote:<hr>Originally posted by michaelxi:
ANY rotors CAN warp. The most common way to warp them is to rapidly cool a HOT rotor. (ie. Car Wash)
[img]images/icons/smile.gif[/img] <hr></blockquote>

I think all these car wash posts - though relevant - are freaking hilarious. [img]graemlins/lol.gif[/img] [img]graemlins/thumbup.gif[/img]

**MichaelXi** · 03-06-2002, 01:15 PM

I persist, because they seem to be disregarded. I mention it, and folks keep asking "WHYYYYYYYYYY", w/o even pondering the fact that RAPID temp change can warp metal in a hurry....
[img]images/icons/smile.gif[/img]

01-10-2002, 09:04 PM	#3
[\]iteshift Senior TEAM Member Join Date: Jul 2001 Location: Akron, Oh Posts: 1,477	Re: Bent rotors, what\'s causing it? Same thing hapened to me. I have 9000 miles on the car and its just my back right rotor. Warped as hell. Breaking at high speeds feels like an earthquake. Taking it in tomorrow. Do they have to special order that part? Howlong should it take the dealership?
$[\]iteshift is offline$

01-10-2002, 09:45 PM	#4
wmudavey Senior TEAM Member Join Date: Oct 2000 Location: Ann Arbor, MI Posts: 3,267	Re: Bent rotors, what\'s causing it? dude u have advance trac?

01-11-2002, 12:05 AM	#5
wmudavey Senior TEAM Member Join Date: Oct 2000 Location: Ann Arbor, MI Posts: 3,267	Re: Bent rotors, what\'s causing it? I did the same thing. REALLY pissed me off cause the dealer didn't catch it. So I got new rotors...but they suck. I am so pissed. I got new ones again. I am now on my third set. They just replaced the rotors this past time and not the pads. They shake like crazy. I don't know if they overtorqued the wheel or what. The rotors are too small for my application anyways. I have traction control and in the snow and ice they heat up like a frying pan. This along with cold weather can really ruin them. I don't know if anything else is damaged but it is making me nuts!!!!!!!!

01-11-2002, 12:23 AM	#6
2001 ZTS Senior TEAM Member Join Date: Jun 2001 Location: Toronto, Canada Posts: 2,542	Re: Bent rotors, what\'s causing it? I don't know how you drive your car and how hard you use your brakes but what can happen, apparantly, is after you come to a hard stop your discs are very hot. If you keep your foot on the brakes the pads will rest on the same point on the disc. The disc itself will cool at a different rate than the portion of the disc covered by the pads. This could cause warpagedue to uneven cooling. Just repeateing what I've heard elsewhere. Seems to me to be an extreme case. Maybe someone else can comment.

01-11-2002, 12:49 AM	#7
SanDiegoBMX TEAM Member Join Date: Apr 2001 Location: San Diego Posts: 195	Re: Bent rotors, what\'s causing it? ZTS, that sounds good in theory and it may help explain my problem if it were occuring out of the blue. But, my guess is that all my problems come back to that faithful night between the curb and I [img]images/icons/smile.gif[/img] . wmud, I feel ya.

01-10-2002, 11:23 AM	#1
SanDiegoBMX TEAM Member Join Date: Apr 2001 Location: San Diego Posts: 195	Bent rotors, what\'s causing it? I hit a curb going 30 or so mph around 6 months ago. The impact was enough to bend a rim and a control arm. I didn't go through my insurance company because the cost of fixing it was lower than my deductible. A month or two later, my rotor became severely warped. I spent 80 bucks, bought a new one and put it on myself. Problem solved for a good 3000 miles, then it happened again. I took my car to a dealership, got it covered under warranty (hook-up), and they replaced both front rotors and both pads. 4000 miles later, they’re bent again. Take it back, they do the same thing, and now not even 2000 miles I can feel it happening again. So, my question is: What else could be causing the rotors to consistently bend? Calipers? Frame? Axle? I don't know too much about cars, but I do know that this is no fun. Any ideas/answers would be greatly appreciated. Moderator, I couldn't decide between the wheel/brakes forum and this one. Feel free to move it to whichever forum you feel this post belongs in. -Ryan

01-10-2002, 08:53 PM	#2
drivefaster TEAM Member Join Date: Dec 2000 Location: Jeannette,PA,USA Posts: 870	Re: Bent rotors, what\'s causing it? Just so you feel better, 80,000 miles and never a warped rotor! If they were going to, they would here in the hills of southwestern PA. I had a problem with the hub that holds the wheel lugs. The hub fits into the wheel bearing, and the driveshaft fits into the hub. The inside of the wheel bearing actually has two sets of races and ball bearings. When I replaced the right side wheel bearing, everything seemed to be OK for about 20,000 miles. Then it started vibrating and I wasn't sure why, was thinking it was the ball joint or strut pivot but they were OK. Just before Christmas I had to put new brake pads on. The driver's side went very well. Then when I jacked up the passenger side, the wheel was very loose and wobbled when I moved it. Not good!! Determined that it was the wheel bearing and luckily had an extra one that I bought just in case. As I got into it more, I found that the wheel nut was loose, problem #1. When I got the hub out of the bearing, the inside half of the hub surface was worn down as if the inside bearing race was locked and it was wearing against the hub, problem #2. The bearing was ruined and not having a new hub laying around, I had to put it back together with the old one. It's OK so far, but I'll probably need a new hub and bearing soon. The point is, I think the wheel nut loosened causing the hub to move in and out and wearing it down. The vibration and grinding that I felt, was like what you'd get with a warped rotor or pads that are worn down. If you have a continuing problem, make sure that the rotors are in fact warped by measuring the runout with a dial indicator. Don't assume that the techs are doing this at the dealership. Also check the torque on the nut to make sure it's tight. Hope my experiences are helpful!!!

01-12-2002, 01:34 PM	#8
noresull [FJ] Specialist Join Date: Aug 2000 Location: Isanti, Southern Canada, MN USA Posts: 5,195	Re: Bent rotors, what\'s causing it? I doubt anything in the front end has warped the rotors. I have only seen rotors warp due to wear, improper/uneven torque on the wheels, or bad driving style. I would really suggest analyzing your driving style and make sure that when ever the wheels are removed they are torqued evenly before complaining to Ford again. The only time I've seen rotors bend or break due to an accident, it was only at the time of the accident. I have never seen rotor issues once they get replaced after an accident.

01-13-2002, 12:45 AM	#9
SanDiegoBMX TEAM Member Join Date: Apr 2001 Location: San Diego Posts: 195	Re: Bent rotors, what\'s causing it? niteshift, a day... maybe two. wmud, nope. Bump bump bump. I'd really like to put on the fascia that I know what I'm talking about when I go into the dealer next time so they don't just say 'we replaced the rotors, so you won't have that problem again' ...for the third time. Por favor, can someone just name of possible things that may cause rotors to warp so quickly (as in my case)? -Ryan

01-13-2002, 02:31 PM	#10
SanDiegoBMX TEAM Member Join Date: Apr 2001 Location: San Diego Posts: 195	Re: Bent rotors, what\'s causing it? What exactly is bad driving style? I drive like any other person. Any un-even torque issues would be at the fault of the dealership that last replaced my rotors... I haven't touched the wheels since. -Ryan

01-15-2002, 05:38 AM	#11
Uriah TEAM Member Join Date: Sep 2001 Location: (Tim)St Louis MO US of A Posts: 877	Re: Bent rotors, what\'s causing it? I re-torque my lugs after any one takes my wheels off and most often I find them way over torqued and uneven. Many people get carried away with air-tools. It is my understanding that even and correct torque on the lugs is especially critcal on 4-lug wheels with modern thin rotors. It does not take long and makes life easier than if I yelled and screamed at my dealer and tried to re-educate all their techs. I think seeing me whip out the torque wrench in their lot has gotten their attention though, as the last couple of times it has come out pretty much right on. [ 01-15-2002: Message edited by: Uriah ]</p>

01-15-2002, 08:58 PM	#12
Uriah TEAM Member Join Date: Sep 2001 Location: (Tim)St Louis MO US of A Posts: 877	Re: Bent rotors, what\'s causing it? I think the manual quotes around 84 but I'm more comfortable around 95

01-16-2002, 12:36 AM	#13
[\]iteshift Senior TEAM Member Join Date: Jul 2001 Location: Akron, Oh Posts: 1,477	Re: Bent rotors, what\'s causing it? so exactly how much torque should I give when putting my tires back on?
$[\]iteshift is offline$

01-16-2002, 01:01 AM	#14
MichaelXi [FJ] Addict Join Date: Sep 2001 Location: Venus Via Knoxville, TN Posts: 24,263	Re: Bent rotors, what\'s causing it? UMMMMmmmmm, Nobody has yet mentioned how rotors can warp if they get wet(ie. car-wash) while hot.... [img]images/icons/smile.gif[/img]

01-16-2002, 06:27 AM	#15
apex TEAM Member Join Date: Aug 2000 Location: New Prague, MN Posts: 708	Re: Bent rotors, what\'s causing it? I just had my rotors replaced at 29,000 miles. I had noted to the dealer that there were deep grooves in the rotor about the width of the pad. He sai this was 'normal'. I told him that I have rotors on my other car with many time that milage that didn't look that bad. Well now the brakes started to pulsate and he sai the rotors are too thin to machine and they replaced them. My wife says the car is a lot quieter. Maybe drivefaaster stumbled on something with the front hub nut being loose. Possible defect/recall? The dealer spent four woking days on the car. Hmmmmmmmmmm.

01-19-2002, 01:34 PM	#16
MichaelXi [FJ] Addict Join Date: Sep 2001 Location: Venus Via Knoxville, TN Posts: 24,263	Re: Bent rotors, what\'s causing it? UMMMMMM, have you pondered my idea??? Any Car-Washing, w/ Hot brakes??? Other 'Jetters have done it. [img]images/icons/smile.gif[/img]

01-20-2002, 12:41 AM	#17
SanDiegoBMX TEAM Member Join Date: Apr 2001 Location: San Diego Posts: 195	Re: Bent rotors, what\'s causing it? Bringing this back to the top. So what I'm getting here that my rotors have consistently warped due to over-torque? That just doesn't sound right. I hit a curb, the rotor problem started after the fact. My driving style hasn't changed from before to after the wreck and I'm assuming that ford is competent enough to put the correct amount of torque on my wheels at least 1 out of the 3 or 4 times they've put my wheels on.

03-05-2002, 12:34 AM	#18
SanDiegoBMX TEAM Member Join Date: Apr 2001 Location: San Diego Posts: 195	Re: Bent rotors, what\'s causing it? Bringing this back from the dead. I suppose things are going well. My rotors are still slightly warped, but it hasn't really progressed at the normal pace. I've made a conscious effort to lay off the breaks after coming to a full stop by a) putting it in neutral and pulling the parking break (gives my f'ed knees a good power nap, as well) or b) lightly applying the break for a short while then letting off (allowing the rotor to rotate a bit) and then applying the break again. I suppose my question now is about aftermarket rotors (slotted)... if my so-called thin rotors are warping, are aftermarket rotors stronger; i.e. less prone to warping? Also, where's a good, cheap place to pick up a torque wrench? Thanks. Edit: Michael, when I do wash my car (sadly, not very often) I head straight from work about a mile away to do the deed. But, I suppose it is a possibility. I'll take that into consideration as well. -Ryan [ 03-04-2002: Message edited by: SanDiegoBMX ]</p>

03-05-2002, 12:41 AM	#19
MichaelXi [FJ] Addict Join Date: Sep 2001 Location: Venus Via Knoxville, TN Posts: 24,263	Re: Bent rotors, what\'s causing it? ANY rotors CAN warp. The most common way to warp them is to rapidly cool a HOT rotor. (ie. Car Wash) [img]images/icons/smile.gif[/img]

03-05-2002, 12:46 AM	#20
Blink_32 Senior TEAM Member Join Date: Sep 2000 Location: Philly Posts: 2,112	Re: Bent rotors, what\'s causing it? <blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by SanDiegoBMX: Also, where's a good, cheap place to pick up a torque wrench? <hr></blockquote> If you find a "cheap" torque wrench, don't buy it! Unless there is a sale on a brand name wrench, your just gonna be throwing your $$$ away. At best you would get a few good readings out of it before it turned to crap. Bad thing is you would never know it. See if you can borrow or rent one locally. SEARS carries all Craftsman line of torque wrenches.

03-05-2002, 08:53 AM	#21
James TEAM Member Join Date: Jan 2002 Location: Little Elm Texas Posts: 234	Re: Bent rotors, what\'s causing it? If you can, stay in the service bay and watch them install the new rotors. When it comes time to zip the wheels back on, be sure that they do not just go in a circle. THey need to make kind of an hour glass figure. And make sure they set the torque at no more that 100 lbs.

03-05-2002, 10:13 PM	#22
fruitport_focus TEAM Member Join Date: Oct 2001 Location: Back to Michigan Posts: 933	Re: Bent rotors, what\'s causing it? <blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by James: If you can, stay in the service bay and watch them install the new rotors. When it comes time to zip the wheels back on, be sure that they do not just go in a circle. THey need to make kind of an hour glass figure. And make sure they set the torque at no more that 100 lbs.<hr></blockquote> When I had my ZX3 in for the wheel brg recall, I told the tech to torque my Konigs to 94lb/ft. Some cars it is critical to torque wheels or warpage can occur. But SDBMX it sounds like you may have undiscovered damage yet. Things to check would be pad wear(is it even), rotor runout(before rotor is replaced), and all other frt end components-hubs, wheel brgs, axle stubs, calipers(for sticking). Just a thought. [img]images/icons/smile.gif[/img]

03-06-2002, 01:12 PM	#23
Shiva Chaos [FJ] Specialist Join Date: Oct 2001 Location: under your bed Posts: 7,331	Re: Bent rotors, what\'s causing it? <blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by michaelxi: ANY rotors CAN warp. The most common way to warp them is to rapidly cool a HOT rotor. (ie. Car Wash) [img]images/icons/smile.gif[/img] <hr></blockquote> I think all these car wash posts - though relevant - are freaking hilarious. [img]graemlins/lol.gif[/img] [img]graemlins/thumbup.gif[/img]

03-06-2002, 01:15 PM	#24
MichaelXi [FJ] Addict Join Date: Sep 2001 Location: Venus Via Knoxville, TN Posts: 24,263	Re: Bent rotors, what\'s causing it? I persist, because they seem to be disregarded. I mention it, and folks keep asking "WHYYYYYYYYYY", w/o even pondering the fact that RAPID temp change can warp metal in a hurry.... [img]images/icons/smile.gif[/img]

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