Questions about rotors
 

I got a question about rotors.

A while back i got a DIY for changing the rear brake pads. It took me a while but i did it.

I went to get an oil change and they said i have to change all 4 pads again. The guy said i probably need new rotors cause my P5's at 80,000 right now.


Is it true that after 80 i should change the rotors? I know it depends on the car and everything, but it's a good idea right?

And if i can change the brakes, i can change the rotors right?? All you do is pull the rotor off (If it comes out easily) and just swap it right?? I'm pretty inexperienced with this stuff, but if i'm capable of changing brakes i can change rotors, right?

Thanks

If you can change pads, you can change the rotors.

Are you saying the rear rotors have never been replaced? If yes, then 80k
is pretty good life.

re
 

damn. idk if the previous owner replaced them. I got teh car at 60k so he might have.

Is there any way for ME to check if their in good condidtion?

Also, am i right in thinking u just take the old rotors out and pop the new ones in?

Yes, but your old rotors are probably seized on unless you live in a dry, warm climate. You might have to hit them with a 16oz hammer for days, torch them until they are glowing, etc.. trust me on that one. Kicking them helps too.

To judge whether they are in good condition, feel them to see if they have any deep grooves in them (you might see grooves, but can you feel them?), and then check the thickness. There's a legal minimum thickness, I think 8mm (it's actually cast into the 'rim' of the rotor, but it's probably rusted/worn off by now) not including the ventilation part in the center of the stock rotors.. don't trust me on those numbers though, that just popped into my head and I have no clue if it is right. I'll try to dig up some confirmed numbers.

Another thing to feel for is if the area where the brake pad actually bites on (only about 90% of the radius of the rotor surface) is dug deep into the rotor, leaving a lip at the outer edge that you can feel.

Then of course, if you feel shaking while braking, the rotors are warped, and you'll want to replace them even if they have none of the above wear signs.

The only extra steps for replacing the rotor involves taking 2 bolts off the back of each caliper, and using a bungee to hang it from the spring. You don't want to hang them by the brake lines, they're rubber and will stretch. No good for brakes ;)

re
 

alright...thanks guys.. i appreciate it

When you mention rotors on a mazda forum the first thought is not brakes but engines. I was misled...

lol wish I had those spinning triangles of doom in my car :(

Don't forget to lube caliper pins while at it!

How can you replace the brakes without removing the calipers?

Those are the steps required to remove the caliper. It's just two bolts more than needed to hinge it open to do the pads.