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Warped rotors after just 10k miles?

I brought my car (Nissan Sentra 2009) to the shop because I had noticed some vibration when braking.
They had installed new pads & rotors just 1 year ago (10k miles).
And now I’m told the rotors are warped and need to be serviced, most likely because I hit a puddle or washed my car in the heat.

Is this a plausible explanation? Or did I get scammed?
Wouldn’t it be possible that the technician did a bad installation job last year which is what caused uneven friction and resulted in the warping?

Thanks.

They probably put the cheapest rotors they could find.There is a difference in quality between a premium rotor and an economy one.How much did you pay for that brake job?..parts and labor

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After 1 year you probably have no warranty on this brake job. I agree they may not have been the best quality rotors or they did get to hot and warped. Rather that use that shop again I would find another and tell them you want really good parts installed .

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Next time you get a brake job, tell the shop you want brake components the meets or exceeds the OEM specificartions.

Update: Raybestos Issues Warning on “Lightweight” Rotor

lightweight versus standard brake rotor

Raybestos, a leading aftermarket brake supplier, has issued a warning about Chinese-made brake rotors that are dangerously thinner than name-brand aftermarket and original equipment brake rotors. The lightweight rotors are being sold in various auto parts stores to unsuspecting consumers as standard replacement rotors. But the thickness of the discs in these “lightweight” rotors has been reduced by increasing the air gap between the rotor faces. This saves about 4 to 5 lbs. of cast iron per rotor, and reduces the manufacturing cost $3 to $4 per rotor. Unfortunately, this trick also reduces rotor strength (which is important to resist cracking and rotor failure), the rotor’s ability to absorb and dissipate heat, and the ability to resurface the rotor safely the next time the pads need to be replaced. For more details, read this warning.

Tester

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Besides replacing rotors with cheap ones, driving habits can contribute to warped rotors. It doesn’t take much for rotors to get extremely hot. Frequent quick stops from high speeds or riding brakes going down a hill can quickly heat up rotors and causing them to warp.

Going to “BRAKES-R-US” you probably have only a limited choice of rotors and many times no-name brands. Suggest you go to a mom and pop shop and you probably will be able to select the brand you wish.

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Sometimes warped rotors are due to improper lug nut tightening. If you can find the original shop, they might give you a break, Best wishes.

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I’ve known quite a few professional mechanics who are convinced that warped rotors are ALWAYS due to improper lug nut tightening

:laughing:

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They told me it was a premium brand (Rambler)… I paid $470 in parts + repairs. And today another $140 for reconditioning.
Does that look right?

Thanks for all your replies!

I just can’t believe that my car was in contact with water a lot. I live in southern California so there’s really not that many rain puddles here.

Isn’t it more likely that it was a poor installation job?

There is really no way to tell what the cause was, just got to go forward.

Never heard of “Rambler” brand brakes . . .

I googled “rambler brakes” and “rambler brand brakes” . . .

The only hit I got was for the AMC Rambler

Unfortunately, this makes me wonder if the shop installed “white box” brakes . . . in other words cheapo parts of unknown and/or dubious quality

There is a brand called “Raybestos” . . . but I have a hard time believing that the guy at the shop mispronounced the name so badly, or that you severely misunderstood what he said

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That’s what I remember he said… anyway, definitely must have been poor quality crap.

Rotor quality is part of the issue. If the mechanic used low cost, off brand rotors, then they probably used low cost off brand pads.

Rotors with thinner cross sections COULD actually be better that those with thick cross sections. Metal casting used to be an art but today it is science. Many factors that affect the quality of a casting include the exact alloy, impurities in the alloy, the height of the riser, and one of the most important is how the casting is cooled. Castings that are cooled progressively following the ideal cooling curve will result in a very dense casting where a poorly cooled casting will be very porous.

A thick porous casting is not as good as a dense thinner casting. But even a good dense casting can be too thin, I’m just saying that thickness is not necessarily the best gauge of quality.

Now pads also are subject to some of the same quality factors. The pads are a composite of a friction material and a resin binder. For any given friction formula, the higher the friction material to resin ratio, the better the pad. But to reduce the resin and increase the friction material requires higher pressures and longer baking times.

The resin in all pads will cook off as the pad is used. Braking generates a lot of heat. The resins will give off residues as it cooks off. More resin means more residues. Some of the residues will stick to the rotors, especially rotors that are more porous. The residues will cause the surface of the rotors to develops differences in the coefficient of friction with the pads that leads some parts that grab more than others. You feel this as a pulsing in the brake pedal or a vibration in the car.

There are a couple of ways to reduce this variation on the surface of the rotor. One is machining like you had done. You can also replace the rotors as many people often do. Myself, I just go out and do a couple of hard 60-5 stops on a lonely road. Go hard on the brakes almost to ABS activation of lockup. Lighten up if either of those occur. Two of those are usually enough to temporarily solve the problem.

I say temporary because as long as you have high resin content in the pads and porous rotors, this will come back no mater what you do. Turns out high quality pads and rotors are cheaper in the long run. Who knew.

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If they used thin rotors to begin with and have now surfaced them this means they are even thinner.

The danger with that is that it is possible at least during a very nasty panic stop that the brake pads may pull the rotor apart or collapse it if the rotor has an air gap and fins between the side.

As for me, I have never, ever heard of Rambler brake components unless as mentioned by db4690 there is a misunderstanding with the word Raybestos which is a quality part.

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When my kids were teenagers, they could borrow my car and warp the rotors in one evening. Fortunately they’re in their 40s now.

Honda and Acura’s (my Cars) have a tendency to get warped rotors, even using OEM rotors. Lots of factors that cause warping as mentioned here.

Yeah, I only wash my car when it’s below freezing out just to make sure I don’t mess up the brakes.

Or in other words, never go to that shop again because they’re idiots.

BTW, they probably aren’t warped. They probably have solidified pad material built up on them that’s making the surface uneven.

The installation job was probably fine since the brakes work, but as others have suggested, they probably used bargain-basement parts.

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How do you people come up with this stuff?

https://www.bendix.com.au/bendix-news/brake-shudder-explained-and-how-fix-it

Tester

With the high traffic speeds and mountains in southern California warped rotors are a common problem.

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Disreputable sources like Consulting Engineer Caroll Smith of Stoptech:

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