Turn brake rotors every time new pads go on?

[Mosey]

Is it necessary to get the brake rotors turned every time new pads are put on? If the rotors are not warped or glazed, it seems to me I could just put on new pads and be done with it.

[Ranchman]

Turning is the "standard" practice - It removes groves that develop in the rotors as they are used. Most brake shops frown on not turning when you get new pads and will also void their warranty on the pads if you don't do it.

That being said, I am NOT a fan of turning rotors. I have had more rotors screwed up by multiple brake shops due to them turning them than I care to remember.

Several problems with turning. 1) unless the machine/rotor is set up perfectly, it can unevenly cut the rotor, leaving some sections thicker than others, thereby leading to warpage. 2) Most brake mechanics I've witnessed over the years throw the rotor on and start turning and do not take the necessary time to make sure #1 above is done. 3) I've witnessed rotors that have been turned unevenly - in that one side is at a different thickness than the other, leading to warpage under use.

I've had a brake shop screw up an otherwise fine rotor so bad that I had to replace it with a new one - which eliminated the problem THEY introduced (shudder when braking.) I also have a truck with ~145K miles on it that I REFUSED to allow ANYONE touch with regards to turning the rotors. Yes, I've replaced the pads a couple of times myself, but even after the miles, my unturned, grove infested, less-than-perfect rotors are within factory specs for minimum thickness and stop the vehicle just fine.

In other words, I guess what I'm saying is that for me at least, while I'm not 100% against turning rotors, I have had far better luck not turning them and simply replacing the pads than I have when I had them turned.

[JohnMiller3]

<font color="blue">...If the rotors are not warped or glazed, it seems to me I could just put on new pads and be done with it.
... </font color>

Agreed...

But, if someone waits past the point of no return... metal against metal... then it has to get turned...

Have you checked the price of rotors lately? Cheap, cheap, cheap... [img]/forums/images/icons/smile.gif[/img]

[Bird]

I've had almost identical experiences with Ranchman's. [img]/forums/images/icons/shocked.gif[/img] Perhaps I might have only a very slightly different opinion about turning the rotors. If obvious grooves have been worn into them from wearing pad into rivets, or if braking has been uneven or a shudder felt; i.e., I could visually see damage or I could feel a problem in braking, I'd have the rotors turned. But the last two brake jobs I've done was because I could see that the pads were worn enough I wanted them replaced, but no other problem. Therefore, the rotors were not turned. However, there can sometimes be a tiny bit of glaze that will cause new brakes to squeak or squeal, so I used a 3" die ginder with "surface conditioning discs" (basically sand paper) to thoroughly clean both sides of the rotor before installing the new pads. One of the jobs was on my own car (85,000 miles) and the other my daughter's car (30,000 miles). [img]/forums/images/icons/shocked.gif[/img] Driving habits and the difference in country living and city living do make a difference. [img]/forums/images/icons/grin.gif[/img]

[Stoneheartfarm]

I'd have to agree with ranchman and Bird. I've changed out a lot of disks. When the rotors get real bad, I'll have them turned once. After that they get replaced. I hate to admit it, but I've left rotors alone that had grooves cut in them. As long as the grooves aren't too serious. (My theory is that one or two hard applications of the brakes and the pads will have similar grooves anyway. So it just makes more surface area. LOL) I would, however, break the glaze as Bird suggested.

Steve

[Autotech]

The reality is that these days most rotors should simply be replaced. Most shops don't bother to measure rotors before they cut them - if they did they would find that the rotor is either under spec, or will be when they get done cutting it.

Personally, on my vehicles, I replace the pads once, then do the pads and rotors the second time. Unless I know the rotors are really cheap, then I just run them to the bone and do it all each time.

Many dealers no longer even have the equipment to resurface rotors - no need for it.

Gregg

[Mosey]

Thanks for the help everyone. I was unaware of the "cheap rotors". It's been a long time since I've bought new ones. I'll probably just put pads on for now, and do the deglazing that Bird mentioned.

[chevdog]

This is just me - because we're a bit too far away from a local shop to turn rotors, I have a second set of rotors that I use when I do a brake job. In between brake replacements I get the rotors that I remove turned at my convenience so they are ready for the next brake job. Brake rotors for my cars and trucks are not very expensive at all, so I can get away with doing this.
I've had good success with Wagner Thermo-Quiet pads in particular, and I usually like to either de-glaze or turn the rotors so the new pads and metal surfaces will seat in together.
Like I said, this is just what I do [img]/forums/images/icons/tongue.gif[/img]

[Alan_L_Texas]

I prefer not turning them as long as there are no symptoms. There are only so many turns in a rotor - why waste one you don't need?