warped rotor or sticking caliper (5S-FE)

[lorakew]

I'm so baffled by this problem:
Car: 2000 toyota camry 5S-FE

My car has been wobbling when pressing the brakes to a come to a stop. When the car slows down (under 10mph), it starts to shake (like a wobble) and it pulls on and off pulsating the brakes. This happens at low speeds. Not sure whether it's the front drivers side or front passengers.

I'm thinking-- within the braking system, i have either a warped rotor, or a sticking caliper. What are the symptoms of a warped rotor or sticking caliper? I tried searching the Haynes without any luck.

I have regular routine alignments and balance and rotation.


Am i on the right track? Could it be a warped rotor or sticking caliper?

[rhandwor]

Try pulling the fuse for the anti lock brakes. If this makes it stop get the antilock system repaired.
Using the brakes a lot in the rain hard will warp a rotor. This usually causes a shaking but not pulsating.

[rhandwor]

Ask your buddy who works at a dealership to look it over for you.

[lorakew]

Originally Posted by rhandwor

Ask your buddy who works at a dealership to look it over for you.

He's always too busy, he has 2 jobs.

I did some online research on the signs of warped rotors:
"A vibration or pulsating brake pedal is often a symptom of warped rotors (but can also indicate that your vehicle is out of alignment). The vibration can feel similar to the feedback in the brake pedal during a panic stop in a vehicle equipped with anti-lock brakes. It is a sign of warped rotors if the vibration occurs during braking situations when the anti-lock brakes are not engaged."

I'm going to replace the rotors, since i believe they are most likely warped. I've had this car for 8 years and never replaced the rotors, and living in the south, and with the rain and heat they probably had it coming.

In the meantime, any suggestions on descent rotors?? I found autozone's "duralast" brand $30. Are they any good?
I'm not looking for performance parts, just a simple exact replacement.

[rhandwor]

Pulsating if the brakes are moving by themselves and feeling your foot move up and down are different types. Buy quality pads bendix or other name brand.
Rotors get a few quotes the better ones are made in the US Advance and AutoZone work satisfactory for normal use.

[Mike Gerber]

A pulsation only when braking and not just moving forward without braking, is usually the sign of a warped rotor. You may also feel a vibration in the steering wheel. The steering wheel vibration will confirm that the warped rotor(s) is in the front. Remove the front brake rotors and replace them or have them cut (turned) on a brake lathe, if there is enough thickness left on them to warrant cutting. Also check to make sure the calipers move freely and that the slide pins are not sticking. A stuck caliper can apply constant brake pressure to a rotor, causing it to get very hot and warp quickly. If a stuck caliper is causing the problem and is not corrected, the warping will quickly return.

Mike

[lorakew]

Originally Posted by Mike Gerber

A pulsation only when braking and not just moving forward without braking, is usually the sign of a warped rotor. You may also feel a vibration in the steering wheel. The steering wheel vibration will confirm that the warped rotor(s) is in the front. Remove the front brake rotors and replace them or have them cut (turned) on a brake lathe, if there is enough thickness left on them to warrant cutting. Also check to make sure the calipers move freely and that the slide pins are not sticking. A stuck caliper can apply constant brake pressure to a rotor, causing it to get very hot and warp quickly. If a stuck caliper is causing the problem and is not corrected, the warping will quickly return.

Mike

When i did the brake job, i noticed the pins were sticking, so i lubed them up with brake pin grease (silver stuff). hmm...
If the pins are sticking, should i just lube them up? or does it require further cleaning out...

[lorakew]

Originally Posted by rhandwor

Pulsating if the brakes are moving by themselves and feeling your foot move up and down are different types. Buy quality pads bendix or other name brand.
Rotors get a few quotes the better ones are made in the US Advance and AutoZone work satisfactory for normal use.

Right now i've got NAPA brake pads that are comparable to the bendix ct-3 ceramic brake pads. I did the brake job myself last year (at the same time i lubed the pins and checked for leaks)

[Mike Gerber]

"When i did the brake job, i noticed the pins were sticking, so i lubed them up with brake pin grease (silver stuff). hmm...
If the pins are sticking, should i just lube them up? or does it require further cleaning out..."

You should be able to move them in and out freely. Were you able to do that after you lubed them? If so, you should be ok. If not, you may need to do further work to clean up the holes they go in to in the caliper mounting bracket. There may be rust in there. This might also require replacing the little rubber boots that seal the pins in that area. What I did once when I had this problem is take the caliper mounting brackets off the car and remove the rubber boots. Then I cleaned all the grease and dirt and rust out of each of the holes with brake clean. Then I took them to a friends shop where we sand blasted the holes for a second or two to remove any left over rust. I sure sand paper wrapped around a pencil would also work. It would just require a bit of elbow grease. Then we blew them out with compressed air and put fresh lube down there. I prefer to use high temeprature disc brake grease. Then I installed new rubber boots. They come with a metal ring that is tapped in to the caliper mounting bracket hole edge. Then relube the slide pins and reinsert them.

Mike

[lorakew]

Originally Posted by Mike Gerber

"When i did the brake job, i noticed the pins were sticking, so i lubed them up with brake pin grease (silver stuff). hmm...
If the pins are sticking, should i just lube them up? or does it require further cleaning out..."

You should be able to move them in and out freely. Were you able to do that after you lubed them? If so, you should be ok. If not, you may need to do further work to clean up the holes they go in to in the caliper mounting bracket. There may be rust in there. This might also require replacing the little rubber boots that seal the pins in that area. What I did once when I had this problem is take the caliper mounting brackets off the car and remove the rubber boots. Then I cleaned all the grease and dirt and rust out of each of the holes with brake clean. Then I took them to a friends shop where we sand blasted the holes for a second or two to remove any left over rust. I sure sand paper wrapped around a pencil would also work. It would just require a bit of elbow grease. Then we blew them out with compressed air and put fresh lube down there. I prefer to use high temeprature disc brake grease. Then I installed new rubber boots. They come with a metal ring that is tapped in to the caliper mounting bracket hole edge. Then relube the slide pins and reinsert them.

Mike

I see... The last time i lubed them up they moved somewhat freely. When I pushed the pin all the way in the rubber boot, it took a quite a bit of force to pull it back out. Other than that, it was sliding okay midway... not sure if that makes any sense. Next week I will change out the rotors and try cleaning out the boots and post from there. thanks for the info.

[jdmccright]

I'll only chime in to say that if you do sand blast anything where parts slide against each other, make very sure you remove all the blast media and contaminants afterwards with a good shot of compressed air and brake cleaner. Any remaining residue can do just as much damage to the mating surfaces.

If it were me, I'd replace any part where rust was present on sliding surfaces...especially brake-related. Once it is rusted, rust will swell and score the opposing surface. And if the rust is removed, then you're still left with a non-uniform surface, resulting in slop or misalignment.

As far as the difficulty in pushing and pulling the pins in and out, remember that the pins are fitted very closely to the slider holes and the brake grease fills in that space in between. Since the pins terminate inside the caliper body, it is essentially a piston. You press it in, and it expells air through any gap to be found. When you pull it out, air has to find its way back in again to relieve the vacuum pressure created at the slider pin's tip.