Brake Rotors Warping

[mdmarauder]

Guys, I'm getting some warping of the front brake rotors. I have 13000 miles and wondering if anyone else has this problem. I don't generally like to turn rotors because it just ends up making them to thin and then you're back at square one. Also, if I do have to replace the rotors does anyone know where I could get a set of slotted or drilled rotors? I'm not trying to replace the calipers by the way.

[Logan]

If the rotors are warped you shouldn't be turning them anyway, replace em. At 13000 miles, I'd be making the dealership do it under warranty.

[MM03]

I have found that brake rotors will warp if the wheels have been taken off and then reinstalled without using a torque wrench to tighten the lug nuts back on. This could be the cause if you've had the wheels off recently. If 1 lug is tighter than another it will put ueven presure on the wheel, hub, and rotor assembly. When the brakes get heated and cooled a number of times then they will warp.

[Macon Marauder]

Yes, I've most-often seen warped rotors after tire service. Such as rotating, etc. Our friendly neighborhood Ford dealer replaced many a rotor under warranty (and some not) when they had a tech that got too happy with the air wrench.

Gotta watch 'em!

[mdmarauder]

The car has never had the wheels off. I will try to get the dealer to replace the rotors. Although, I just went through this with a 2001 Taurus that we have and they said Ford will not let them replace a rotor unless they have turned it enough times to where it is too thin. Don't think I want to go through all that. Any ideas on aftermarket rotors?

[WolfeBros]

I have to go with what Logan said. Its a new car, 13,000 miles.....its a warranty issue. Go get you new rotors.....don't let a dealer flim flam you.

As far as aftermarket rotors, cross drilled, slotted ect.....
Unless you are going to shell out some big bucks for performance calipers & pads to go along with them........your wasting your money IMHO.

[Fourth Horseman]

Geeez. Guess I'm going to start busting out the torque wrench when I tighten down the lug nuts. I had no idea that this could lead to warping.

[RF Overlord]

Fourth:

In the good ol' days of drum brakes, it wasn't much of an issue. Disc brake rotors are more sensitive to improper tightening. The procedure I was taught was to tighten the lugs in criss-cross fashion to half the recommended torque, then go around again to the full torque. Using an air gun to tighten the lugs is acceptable only if the max torque the gun is set for is below the max recommended torque, and only if the person using it is trained properly. I had lots of rotor-warpage issues with my T-Bird until I replaced the stock units with Raybestos aftermarket ones and stopped letting tire people use an air gun.

[Fourth Horseman]

Yup, I always criss-cross tighten the nuts, but I've been doing it with an air gun. I'll use my trusty torque wrench from now on and do it right.

I never had any trouble with my '97 T-Bird, but I'd rather not take any chances.

[engine23ccvfd]

So what is the correct torque pressure for the wheels...?

[Fourth Horseman]

I'll look it up in my shop manual tonight and post it if nobody beats me to it.

[jgc61sr2002]

Most shops use an air gun and the lugs nuts are generally overtightened. Not only does that warp your rotors but if you have a flat you can't get the lug nuts off. I deal mainly with Cosco for tires and they always use a torque wrench.

[Fourth Horseman]

95 ft-lbs according to the book.

[drkknight196]

Would you believe my L/M dealer's service shop doesn't use a torque wrench nor torque sticks? I had a chat with the General Manager about this and suggested a change in procedures might save them a lot of aggravation and $$ in the long run. Meanwhile, I bought a 1/2" drive Craftsman torque wrench and keep it, a short extension, and socket in my trunk. I check my lugs after EVERY rotation/balance. It's amazing how some of those guys mistreat your wheels! That's the main reason I went to McGard locks AND lugs -- the dealership kept tearing the tops off the OEM lugs! Surprisingly, I've had NO problems with my rotors, but if they were warped after 13K, you can bet your boots I'd have a new set from Ford gratis! Also, I put aftermarket slotted/drilled rotors on my 2002 Durango, but ONLY WITH the recommended MATCHING pads. JM2centsW

[hrtn_monky]

does anyone have excessive brake dust on any one wheel? I have excessive dust on on the left front, complained to the dealer, they said all is normal. I have to bring it back now because the cleaning process has now scratched the s*&^ out of my wheel :-(

[Bigdogjim]

Dealing with Ford rotors on the fleet of E-vans, heat is the big emeny. Not trying to say that your locking them up and overheating them, but, heat is a major factor. I have seen it time and time again.

[mtnh]

Heat is the enemy, as the big dog says, but rotors can take plenty of heat and stay true a and flat. Quite a few years ago now, I went into my LM dealer complaining about rotor warpage on my 1993 Merc GM. The SM told me this story, and I walked away from that garage shaking my head in disbelief, chaulking it up to yet another BS story from a dealership. A few years later, I began to believe that story and am now convinced of its truth. OK, the story, without further BS: This guy (the SM) said that the rotors were becoming warped due to un-even heat dissipation, caused by keeping the brakes clamped onto the same part of the rotor surface throughout a controlled stop, like at the red light. On your approach to a red light, you are running on your brakes to slow down and stop. Then, you set there with the brakes holding the car while you wait at the light, and the rest of the rotor cools down, while your brake pads hold the rotor still and keep the heat concentrated in that spot. For this, we can thank, in part, our wonderful automatic transmissions and torque convertors, for passing along the forward crawling power, which necessitates our standing on the brakes whenever the car is in drive and stopped. Whenever I am stopped now with an automatic (which isn't often since 1994), I allow enough room for the car to be stopped, inched forward a foot or so, and repeated for the minute or so that the lights are red. I give it around 10-15 seconds in any one spot before rotating the rotor out of the hot brake pads.

On the other hand, on my manual-equipped cars, there have been days where I put the car in the garage after a commute through the twisties, and actually smelled smoke coming out of the front pads and rotors, and have yet to warp a rotor on either my old Peugeot Mi16 (1994-2001) or my LS, 2001-present, both manually equipped cars with very good binders from the factory. Both cars are equipped with hand brakes for parking, which I use at stop lights if the ground is not level.

Anyone else ever heard of the un-even brake heat dissipation theory?

Mike

[MM03]

mtnh, I have heard of this and sometimes if I feel the brakes are extreamly hot I will let the car roll a few feet after stopping and then just apply enough brake to hold car still. If wheel torqe is uneven that is when the rotors are more likley to warp when the rotors are heated. There is no way stop brake rotors from getting hot. Thats what they are designed to do. They take the kenitic energy ( a moving car) and transfer that into the rotors as heat.

[bugsys03]

if i have heated them up coming to the light i just put her in park and leave my foot off the pedal until it turns green. that way the pads have no direct contact with the hot rotor and no warping

[SergntMac]

Originally posted by mtnh
Anyone else ever heard of the un-even brake heat dissipation theory? Mike

Yes, I first heard it about 25 years ago, and it was a genuine problem that long ago. Hard to imagine that it's still a problem.

One one thing I do agree with in this entire thread, is that if you're going to push the limits with your MM, get better hooks. A top drawer upgrade from Baer should run you 1500 bucks, but it's quite an upgrade, performance and cosmetics, and well worth it...IMHO.

www.baer.com

[TripleTransAm]

Originally posted by mtnh

Anyone else ever heard of the un-even brake heat dissipation theory?


Yes, I've heard of this, but I honestly think you REALLY have to heat the buggers up to get them to warp that bad only from holding the brakes on the same spot too long.

Within 2000 miles of purchase (brand new), my 1998 T/A's front rotors were warped already. And I *KNOW* I took it easy on the car while it was new. This was due to the dreaded 'torque' warpage that has been mentioned here, I believe they came improperly torqued from the factory.

On the other hand I then also proceeded to enjoy repeated lapping (road course) sessions and lots of 1/4 mile action (drag strip), once the rotors had been cut slightly. I never really paid much attention to proper cooldown, and eventually they did warp again after one particularly heavy hot-lapping session at the drag strip (repeated 1/4 miles over and over and over and....).

One other theory I've heard of is that excessive brake pad material gets 'burned' onto the rotor and the pulsations are similar to that of a warped rotor. This *may* be something valid, as I recall going into a lapping session with slightly-pulsing brakes, but finishing the event with totally smooth brakes once again. Now, I seriously DOUBT my T/A has enough clamping force to shave a couple of mils of metal off a thick 12 inch rotor!! So maybe there's something to this brake material thing...