New discs using existing (nearly new) pads

Stallingrad

Just bought a 2015 Superb.

I've got a slight grinding from the front brakes under braking, the disks are not mirror smooth either with (very) minor scoring ad corroded on the lip. So I want to replace them. Issue is the car has relatively new brake pads, cant be more that a few 1000km on them.

Can I get away with replacing the disc using the existing pads, and will the pads re-mate easily enough with the new surface?

Cheers.

Renegade Mechanic

Stallingrad wrote: »

Just bought a 2015 Superb.

I've got a slight grinding from the front brakes under braking, the disks are not mirror smooth either with (very) minor scoring ad corroded on the lip. So I want to replace them. Issue is the car has relatively new brake pads, cant be more that a few 1000km on them.

Can I get away with replacing the disc using the existing pads, and will the pads re-mate easily enough with the new surface?

Cheers.

Fraid not. Anywher the pad adapted to the surface of the old disc will be shown on the new disc through rusty rings of non-contact that will persist as a cyclical battle between rust and pad material..

Stallingrad

Renegade Mechanic wrote: »

Fraid not. Anywher the pad adapted to the surface of the old disc will be shown on the new disc through rusty rings of non-contact that will persist as a cyclical battle between rust and pad material..

Great advice, many thanks.

extra-ordinary_

Renegade Mechanic wrote: »

Fraid not. Anywher the pad adapted to the surface of the old disc will be shown on the new disc through rusty rings of non-contact that will persist as a cyclical battle between rust and pad material..

The pad won't correct itself and the rust will continue to eat high spots into the pads??

Renegade Mechanic

extra-ordinary_ wrote: »

The pad won't correct itself and the rust will continue to eat high spots into the pads??

In my experience, yes
Say you have 10% of the pad not in contact with the disc through grooving. It's by no means dangerous, but the other 90% will have to wear down before the first 10% meets the disc. That takes time, during which you park and the disc rusts. It rusts more on the uncontacted rings, this rust wearing just a bit into the pad during the start of the next day, prolonging the time significantly until you reach full contact - by which time, the disc has taken some of the pads form, becoming grooved itself.

w211

The new rotors means always the new pads too. The new pads does not cost very high price if you can order from UK/Germany.

Mooretaxi

If you’re already spending cash replacing the discs then a new set of pads Wouldn’t break the bank, however, the old pads can be rescued by using a sheet of 40grit sand paper. Sand paper on a flat surface and rub the pad of it in a circular motion until any slight grooves are gone, to check that you’ve sanded them evenly , place the pad on the flat surface with the friction side down and measure the height on all four sides

Stallingrad

Cheers folks, will go with new pads and disk so, this is not a premium car so parts are very reasonable.