I know this topic has been beaten to death but after searching, I still have a few more questions. So I need new brakes in the front. I have just over 36K on the clock. How do i know if I need new rotors? I went to Pep boys and bought new ceramic pads and rotors and I asked the douchebag at Pep Boys to just give me a quick ball park look at my rotors to see if I need them turned/buy new. He was lazy and said there is no way to tell unless i pull it off and micron it. I said just give me a gee wiz look, and he said sorry. So, how do I know if i need new rotors? i bought them so that I wouldnt have to go back if I did and if I dont, I will just keep them for next time. they are not grooved very much, but it is always just safe to change em out?

 

Funny stuff. He couldn't give you a Gee Wiz look because that's the look they have on all the damn time!..lol
However, he is right about the micrometer thing except you would need to put them on a rotor lathe for balance check.
As far as rotors, they should be cut if they are excessively grooved. If they are warped and shimmy when your getting off a highway ramp they should just be replaced. Factory OEM rotors are better than anything you buy aftermarket. They are plenty thivk enough to even have cut which usually costs about $10 per rotor. Aftermarket rotors should just be replaced and never cut. If the rotors look pretty good and don't shimmy when you hit the brakes, just slap the pads on, lub up the slides and call it a day!

 

By cut you mean "turn" right?

 

Correct. They generally do 2 cuts on a gradual basis.

The rear rotors are more expensive because those must be cut on 2 diff areas. For the pads(exterior) and for the emergency shoes(interior)

 

I have never cut the surface for the e brake and if its groved or rusted badly you replace them. the e brake only holds the truck they can be all rusted up just sand the rust down and make sure the e brake shoes are ok . Remember they only hold the truck when stoped . Turning the e brake surface sounds like something that pep boy's or those type of stores that tell you you need calipers when you do a brake job or if you replace all the parts in your ft end and they will warr it for a lifetime

 

For most people, you are correct, they only use the emergency brake as a parking brake. However, it can also be used as its name states, in an emergency. If your hydraulic system fails (a VERY rare occurrence if properly maintained) and you have no brakes, you can use the emergency brake to slow you down (although it will probably take you a loooong time to slow down). In that case, you would want the emergency brake to function properly, so getting the surface turned is probably a good investment if it's really bad - or just replace the rotor and get a brandy-new one already done.

To answer the original question, the Pep-Boys guy was lazy, but correct. You can't tell if you need new rotors without measuring them. However, it doesn't hurt a bit (other than your wallet) to replace them if you want to. He should have been able to tell you the price of new rotors by simply pressing a few more buttons on the computer - after all, he had already looked up the pads you needed.

 

Get autozone blanks and call it a day. They're cheap ($30-$40 each) and if they warp within two years they get replaced for free. OEM's are overpriced like everything else. Powerslot also makes a good slotted rotor...if that's what you're looking for.

 

Fellas, He is talking about the front! I barely mentioned the rear and your all jumping on the rears.

Stock OEM rotors even after they are turned are a better and stronger rotor than Napa's or Autozone's best one's. I would either have them turned if they are grooved pretty bad, if not then just slap the pads on and call it a day. If they are warped and shimmy when you hit the brakes, then replace them because you may not be able to cut them and plus they have already heated up and weakened.

 

my friend's mom was driving his cherokee when the brakes went out. put on the e-brake, got nothing but a 'brake material burning like hell cuz it can't do what you're asking it do' smell.

 

There's always something better...that doesn't mean they're the better choice. I've never had a prob with autozones duralast rotors and for the price you can't beat them...with warranty.