If your rotors warp, 90% of the dealers are going to blame in on your non-OEM pads. I guess it depends on your relationship with your stealer, but having to buy new rotors is a real possibility.

Yeah, I'd agree with that. Are you saying, though, that non-OEM pads (not track pads) are more likely to cause the rotors to warp? Or, is it a case of worn rotors warping if they are close to or under the minimum thickness spec? Part of doing the brake pad replacement is evaluating the condition of the rotors, but it isn't something that everyone will do. Not many will have access to a good lathe to get the right surface finish, if required.

Back to the original poster's question, if the rotors warp with new pads, were they not likely in need of replacement in any case, and shouldn't they have been done together with the pads?

Jeff

Buy a set of good replacement pads (Axxis or Mintex) and rotors (Brembo) and put the originals in a box on the shelf. If you ever need to put them back on for any reason, you have them at close hand.

By saying that it is a "real possibility" it kind of makes it sound like this is a likely outcome. On the contrary, it's my opinion that while it is possible for rotors to warp, it is unlikely that they will.

I have been using the EBC pads that have significantly reduced the brake dust with no squeal (eventually)

I dropped the car in and the brake company warned me that the rotors should really be machined as the OEM pads are likely to have left some wear grooves.

Thinking that this was the usual "pad out the bill" attempt I declined and drove away with my new pads.

I was back the next day, deafened by the noise as the new pads were squealing like a banshee.

They were right, and you could see where the new pads were not touching the disk. It was causing a slight vibration that became a squeal under braking when they warmed up.

Personally, changing pads DIY is a doddle but if you need the rotors done it kind of defeats the purpose.

I have only ever warped rotors when they are being pushed (track) with aggressive pads making up for undersized/spec'd rotors and not being allowed to cool down.

Normal day to day use would be extremely rare........

the "real possibility" I'm referring to is you buying new rotors in the event they warp. I've had 2 independent BMW service shops both tell me that the likelihood will increase with low dust pads. but, i have no expertise on matters of brakes and lots of people here on the board seem to be doing fine with them. So, in other words, :dunno:

Rangerfan: Lots of advice for your short question.

All of the above is part of the qualification that comes along with it being a straightforward DIY job. As LVR says, dropping in a set of pads is very simple. If the rotors are in very good shape, with no glazing, heat spots, wear grooves, etc, or if you are replacing the rotors, not so much to worry about. If you are keeping the rotors, you need to measure them and see how much metal is left. In general, warping rotors (other than on the track) can be a result of inappropriate pads for the street, failure to bed the pads in, hard driving, too little metal left on the rotors so that they are too thin, etc, or a combination of the above. Warping rotors on the track is about pushing the design limits. I haven't warped rotors in my very limited track time, but I did boil the brake fluid once in a Ferrari that wasn't mine, at a track day event.

If you use street pads (Axxis are good...), the rotors are in good shape or you replace them, you bed the pads in properly, then you are good to go. Hope all that helps.

Jeff