Replacement time, and brake bolt rubbers question

[BennyLava]

Hi all. Had a couple of questions about my 2009 Sedan brakes. I went to put new pads and rotors on it, but I'm finding the job to be a bit odd. First off all, the car has 152k miles on it, and the pads and rotors look to be fine. I bought the car with only 40k on it, so you know these must be the factory rotors and pads. Cause I've certainly never changed them.

But, I faintly started to detect that warped rotor wobble. It only seems to make itself known when you're at a certain speed, during braking. And it doesn't always do it. So its pretty faint evidence for the warped rotor wobble, but I have noticed it here and there. So I said fine, these brakes have 150k on them, may as well go ahead and replace the rotors and pads.

Well I get in there, and the rotors seem to be pretty flat, and the front side doesn't even have any lip, at all. The back side does have that small lip that old rotors start to get. But its not very big. The pads, seem to have at least half life still left on them, maybe even 2/3 life left. So at least by the looks, I'm a bit confused.

So what is your opinion? Should I just go ahead and replace them, even though there is some evidence that they may still be good? Should I perhaps wait another 10k, or 20k miles and see what happens? Or should I go ahead and do it now? Personally I dislike the idea of replacing something that doesn't need to be replaced at that time.

Lastly, I have another question related to the rubbers that go along the bolts that hold the top of the caliper, to the bottom. Those bolts that on some cars, you will take them out and clean them and put new grease on them, whenever you do a brake job on the car. I think they're called the caliper slide pins. Anyway, on the Yaris they seem to be actually attached to the caliper, by way of their rubber dust guards. How do I get these off? I tried pulling them out really far, but I can tell that if I continue pulling, it will tear the rubber guard. What do you do about greasing up these bolts, if anything?

[BennyLava]

Somebody... anybody?

[dogsridewith]

"...the bolts that hold the top of the caliper, to the bottom."
?

[WeeYari]

Lastly, I have another question related to the rubbers that go along the bolts that hold the top of the caliper, to the bottom. Those bolts that on some cars, you will take them out and clean them and put new grease on them, whenever you do a brake job on the car. I think they're called the caliper slide pins. Anyway, on the Yaris they seem to be actually attached to the caliper, by way of their rubber dust guards. How do I get these off? I tried pulling them out really far, but I can tell that if I continue pulling, it will tear the rubber guard. What do you do about greasing up these bolts, if anything?

Just compress the rubber boot toward the caliper away from the head of the glide pin head. There is a groove that the boot will pop out of and the pin will then be able to slide out free of the boot.

[SirDigby]

yea. the rubber is stretched into a groove. be gentle. grease them pins good!
as to the rotors; if you have a second car, you can take them you get measured/machined at a NAPA or some other parts stores as well as machine shops. the parts stores will have the measurements on their computers, the machine shop will be able to measure with the specs you pull of the internet. (idk what they are)
you can return the rotors to where you bought them if you don't use them. if you keep them, store them upright, like books, to keep them from warping. (most everyone stores them improperly, even parts stores. it's a good idea to get NEW rotors machined in some cases)

[BennyLava]

If you keep them, store them upright, like books, to keep them from warping. (most everyone stores them improperly, even parts stores. It's a good idea to get NEW rotors machined in some cases)

Never knew that. I'll do it.

As for the little rubber boots on the bolts...

So yall are saying to just sort of gently pry them off the bolt? And that they will sort of just pop out of a grove, on their own? The boot doesn't need to be twisted in any way?

[BennyLava]

bump

[dogsridewith]

Sounds like the same arrangement as my 89 Tercel and 91 Corolla. The bolt is clamping the slider cylinder (pin) which has the grooves, so the bolt is out of the picture when dealing with the boots. You push the slider so it is sticking more out of one side of the caliper body and starting to stretch the boot. Then, push the boot back towards the caliper and out of the groove in the pin. Then can push the pin through the caliper (not letting it get stuck in the pin groove), stretching the boot on the other side of the caliper. If a pin is really frozen, I've freed them by rotation with pliers gripping the very end.
What do people like for grease? One shop showed me a tube of ceramic grease when I asked about lubing sliders.

[SirDigby]

yea. groove on caliper, groove on pin. can be popped off on both sides easily. you can use a little screwdriver or a NOT sharp pick to pull up the edge it you can't squeeze it off. if you are really scared you can just buy new ones and just yank on the sliders and not worry about damage. I think new boots are like $4 each.

[BennyLava]

Thanks all. It looked like those rubber boots would just keep stretching until they broke

[tmontague]

Check the boot for flexibility. I'd recommend just buying buying replacement kit and installing new ones. That way if it tears you're not stuck.

Use rubber safe grease only and don't over apply it. I use rubbing alcohol to remove the old grease from the slider pins and it worked well.

I'd do that first and then see how the brakes are acting.

[SirDigby]

Use rubber safe grease only and don't over apply it. I use rubbing alcohol to remove the old grease from the slider pins and it worked well.



I use sil-glide. it's a good non-drip, waterproof high temp grease. it's also good for many other moving parts too like door jams and sunroofs. and it's clear colored.
NAPA $6