Does Lexus want the rotors to be resurfaced (turned) on or off the car ?

 

They don't say either way in the service manual. They generally don't want to turn them unless there is a deep score or some other kind of damage. I never turn them if I can avoid it. It only reduces service life in most cases. My dealer (wisely) did not turn mine when I had the alternate pads installed.

 

I thought it is recommended to turn the rotors when you change the pads.

 

No. It is not recommended unless the disc surface is damaged or deeply scored. It's a myth that they need to be turned.

 

To answer your question, it is always best to turn rotors ON the car as this takes into account any imperfections on the hub surface that the rotor sits on for a true surface.

 

does anyone know if all Lexus dealerships are equiped with the machine that turns it on the car?

 

I can think of a lot of reasons why this is not the preferred method.

 

no, mechanics do not necessarily resurface rotors when new pads are installed...

they resurface rotors if:
the rotor has a lip on it
they are concerned with making noise
the customer is complaining about noise
the pads are very agressive and have left a step on the inner edge of the rotor
there are grooves in the friction surface

 

I would prefer to just buy new rotors instead of having them turned. The fronts are just $227. However, if I had to turn them, I wouldn't want it done on the car. If you do it on the car, then you have to be super careful not to change their orientation on the hub later. If you remove the disk, then put it back on in a different orientation, they could vibrate. I had to deal with this when I had an "on car spin balance". It was GREAT until I rotated the tires, then it was horrible.

 

I just had my rotors TURNED this weekend. This most likely will be the last time i will be able to turn them, since the rotor was so deeply groved.

My breaks were down almost to 1mm.

I'll just by a new set after 20k more miles, no bid deal....