Tried taking my rotors off today but the two bolts that are holding the caliber is a pain in the *** to turn. Soaked the bolts with WD, still wouldn't move. Used my jack and was able to get one off but the rest wouldn't budge. My hands are hurting like a *****, not knowing what else I can do to loosen the bolts (besides an impact gun or a breaker bar) I put everything back and start calling local shops.


Most of the shops I called advised me not to turn my rotors because they are made thin. I have never turned my rotors and have 55k on the car. I also drive my car hard. Would it be smart to turn them? Or just get new rotors? The pulsating brake pedal is really annoying...HELP! Thank you.

 

The two bolts can be hell. WD40 is a good lubricant, but a poor anti-corrosive. I recommend PB Blaster. Let it sit overnight.

I recommend turning rotors. Rotors must have minimum thickness AFTER turning. 55,000 miles on rotors doubt this will happen.

 

definitely try the pb blaster, I would just go ahead and replace them while your there.

 

Are you saying I wouldn't be able to turn them because it has already been 55k miles?


Replacing the rotors would be better than turning them?

 

Maximum allowable rotor wear is 2 mm.

So minimum allowable thickness is original thickness minus 2 mm. That is thickness AFTER turning.

 

You should need rotors, and get a nice 22mm wrench and a 5 pound sledge. The bolt will come right off.

 

You have the solution right there. It's a piece of pipe.. like $5 from Home Depot.

 

Front left





Front right

Looks to me my rotors and pads are in good shape, what do you guys think? I did however, purchased duralast rotors and pads just in case I am wrong and they do need replacing.

 

Should just buy fresh rotors. I plan to asap, I'm at 55k also and I feel ya man, my rotors warped at like 21k and I just dealt with the brake pedal vibrating. I can't wait to replace them, I know I'll really love driving it even more.

 

Pads have lots of miles on them. Cannot tell about rotors unless I measure them.

 

I decided to put the new rotors and pads on. The vibration and the pulsation from the break pedal has disappeared. Braking feels a lot better now, I should have done this sooner...I also used a metal pipe laying around in my garage to give me more leverage with the nasty two bolts that holds the calibers. Wish I saw that metal pipe the first time I did this...

 

I always use a wrench on the caliber bolts and hit it with a rubber padded, short handled sledge hammer. Never fails. Essentially, a poor man's impact wrench.

To prevent future rotor warping, use a torque wrench when tightening your wheels' lug nuts. Too often a tire jockey will just hit the lug nuts with a pneumatic and cause the rotor to warp the instant it receives any brake pad heat. Any time I have my wheels put back on "professionally" I loosen and retorque the lug nuts to spec before I leave the shop.

 

Is it my imagination or does it look like the rotors and pads are wearing a little unevenly. Are the calipers free to move on the bolts as they should?

 

I been meaning to go out and get a torque stick. Just to have that insurance that everything is in spec. I usually tighten the lugs by hand first, drop the car until the tires touch the floor and tighten it again by standing on the lug-nut wrench. Not the smartest thing to do IMO but I still do it . Maybe that's why my rotors were warped.


Not sure what you're talking about. What do you mean by are the calipers free to move on the bolts?

 

Torque stick is a joke, they are crap.

 

"Not sure what you're talking about. What do you mean by are the calipers free to move on the bolts?"

Looking at this picture, notice how the part of the rotor to the left of the vents is thinner than the part to the right.


Looking at this picture, the friction material on the left pad is slightly thicker than on the right.


Looking at this picture, you can see the caliper has pistons on only one side.


In order for the pad on the other side to exert pressure on the disc, the caliper must be free to move as the brake is applied. Some calipers, like the one below, have pistons on both sides of the disc, so the pressure is balanced without movement of the caliper.


Looking in the service manual section BR, the exploded view of the components for the standard brakes shows "sliding pins" which are coated with grease during assembly. There are boots over the pins to keep the grease from getting washed away.

The Brembo brakes have two pistons in each side of the caliper, so they don't have a sliding pin arrangement.

 

Looking at the images, not much is really wrong. The variance in rotor plate thickness is relatively normal. They are not always even in thickness as thermal analysis will show one side cools better than the other. The "hot" side gets slightly more thickness to reduce thermal distortion. It is important that both plates are at the same temperature so the rotor expands evenly as it warms up.

The variation in pad wear from inside to outside pads should always be watched, but some (like the small amount in the photos) is normal for sliding calipers. This is less likely to occur with fixed caliper as they have opposed pistons.

Chris