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Rotor Ruination

I really need some help in the worst sort of way. I own a 1998 Toyota 4-Runner SR5 3.2 with automatic, 2-wheel drive. I got the vehicle in ?06 w/approximately 161k miles. It?s been really good except for the front brakes. I now have 216k on the vehicle and I?ve had to have the rotors replaced four ? that?s right ? four times. They needed replacing when I got the vehicle so I did that right away. I had run-of-the-mill quality installed at that time. But around 12k later it was bucking like a bronco when brakes were applied. The last three sets have been top of the line w/warranty. But I know this just isn?t right. I drive my car with care and have it serviced regularly. I talked to some retired mechanics and they said it had to be heat causing the rotors to wrap. The last shop did in fact check the rear brakes and found they weren?t engaging enough and adjusted them. We went ahead and installed the best rotors he could get from his parts house and things were fine until about 12k later. Now, it?s acting all wobbly again. Another consumer told me he hadn?t had that problem with his ?97 4-Runner, but he understood the emergency handbrake needed to be used from time to time to keep rear brakes adjusted. I?ve tried that, too, but no dice. I know one thing: I don?t know what to do anymore. Could someone please provide some advice on correcting this recurring, expensive, unnecessary predicament?

Rotors these days are thinner & cheaper than they used to be, and this problem is not uncommon. Though it does sound like you have ended up with top quality rotors - such that it is.

Who keeps replacing these rotors? Try another shop.

Here are the most common reasons that brake rotors can keep getting messed up:

  • improperly torqued lug nuts. The lug nuts should be torqued to manufacturer specs and need to be tightened evenly. Don’t trust that a shop does this right unless you watch. This has to be observed any time the wheels are removed.
  • dirty hub/mating surface with rotor. The place where the rotor mounts gets all messy, esp with rust. The hub & rotor each need to be perfectly smooth. The amount of unevenness on a rotor that you can feel through your brake pedal is tiny - like you can’t tell by looking - not even close. Even very small bits of rust or corrosion will lead to rotor problems.
  • sticking calipers. The brake calipers that hold the pads have some kind of sliding mechanism and each time the brakes are done these should be checked & cleaned & lubed. The other problem, however, is that the pistons might be sticking in which case you need new calipers. At 216K this wouldn’t be odd. This is the kind of thing that produces excess and uneven heat.
  • Less likely but perfectly possible: worn front end parts - minor but enough to cause minor vibrations or such when braking - over time produced unevenness with the rotor.

Big Dan, Four Brake Jobs In 55K Is BS. That’s What It Is.

"They needed replacing when I got the vehicle so I did that right away."
Maybe that’s why it was sold to you, a continuing brake problem.

Cigroller gives some good ideas. You’ve put a lot of money into brakes. $50 to $80 more will buy you an infrared non-contact thermometer. Sears has a craftsman one in this price range ($80 - only goes 0F to 1000F). You can get more gun for less money. I got an ATD-701 on sale at auto parts store for $50 (ranges -76F to 1,022F). The wider the range from below zero to above say 1000F, the better.

You can stand there and shoot your rotors (right through thr wheels if they’re slotted) with this thing and check the temperature to tell if they are too hot. You can even try running down the road and coasting to a stop (no brakes) and then checking. There might just be a problem with the hydraulic side of the braking system, calipers, master cylinder, booster, collapsing brake hoses, etcetera. Are the calipers still “floating, sliding” each time brakes are required? The gun could help you to know when you’ve actually solved the problem too, by checking for heat after attempting a new repair.

So for about the price of a brake rotor or an hour labor you can have a new fun tool. It can be used for engine heat issues , air conditioning, and around the house. I use mine to help find leaks in insulation and air infiltration in my house.
This brake thing is B.S. So take a brake break and have some fun.

This is just one of many tools out there: (It’s the one I bought on sale, locally.)

Details would help.
When you get this brake wobble/shudder/whatever do you mean you feel it in the steering wheel or is it in the brake pedal/seat/car body?

While I won’t get into the technical explantion for the moment, if the problem is in the steering wheel then you should consider something else besides the brakes being at fault. A brake wobble does not necessarily mean the rotors are the cause.
It could be a loose wheel bearing, worn ball joint, tie rod, tie rod end, control arm bushing, etc. At 200k miles anything is possible.

The rubber piston seal of your disc brake piston acts as a retracting mechanism causing the piston to return in its bore. Not all caliper “stickin” is caused by friction on the sliding pins.Has anyone been talking about this with you?

Yes, sir, you can definitely feel the unevenness in the brake pedal; you can see the auto tranny shifter moving to and fro. I was raised on a farm and while I’m certainly not a mechanic, I’m familar with basics. The car doesn?t vibrate in the steering and the tires have always worn evenly. I don?t romp down on the brakes when I stop. I really appreciate your help. If you need any further info for clarification or anything at all, please let me know. Thank you for your time to help me.

I recall reading a Click and Clack newspaper column about a car they had in their shop with a recurring warped rotor problem. They finally attributed it to the car (a Volvo, IIRC) being washed immediately after being driven. The hot rotors didn’t like being sprayed with water, and they warped.

I believe they finally figured it out because the problem was occuring only after the primary driver’s wife used the car. He hand washed his “baby” in the driveway on Saturday mornings, but his wife would run it through automated car wash when she had use of it.

Just something to think about.

Whenever there’s a pulsation in the pedal, etc. this usually points to the rear brakes.
Take the vehicle out on a smooth stretch of deserted road, run it up to about 40-45 MPH and then slowly bring the vehicle to a stop with the park brake only. Do NOT touch the brake pedal. If you can feel a pulsation or shudder in the seat then the problem is the rear drums and those people have been barking at the wrong end of the car.

Drums can distort due to age/wear/heat and very often by someone overtightening the lug nuts. Brake drums are far more susceptible to warping than rotors and the wider the lug bolt pattern the easier they are to distort.
The cure is to machine the drums and reinstall the wheels while being careful to properly torque the lugs. And make sure that anyone in the future who removes those wheels also torques them properly instead of hammering on them with an air wrench.

We have had many discussions about water on the rotors causing warpage. The overwhelming viewpoint from this Forum is that it is not the cause of rotor warpage. Most felt the main cause of rotor warpage is over tourque of the wheels,with poor rotor design followed by cutting the rotors to much. Water on the rotors is a urban legend.

Some on the Forum don’t believe in rotor warpage at all.

Thank you, sir. Will give it a try and let you all know what I find out. Thanks for all the help.

“Water on the rotors is a urban legend”

“Some on the Forum don’t believe in rotor warpage at all”

You need to broaden your horizons beyond this forum.

I’ve detailed, several times, a way to check the brake fluid flow from an open brake caliper bleed screw; but, no one ever reported that they did it. So, take a short cut, and replace both front rubber brake hoses at the wheels. They aren’t that expensive, are they?

Forget the car wash bunk.
How does Click and Clack or anyone else propose to keep rain water, snow, and ice off of the rotors?

35 years mechanic with GM,BMW, HONDA,KIA ASE certified.Worked with Dealer, Indy,Chains ,self employed in both Europe and USA,been around a bit.

You’ve tried adjusting the rear brakes using the parking brake lever method, but have the rear brakes been checked? They may be worn out or frozen. This will overload the front brakes and, well, you what happens next…

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