front rotor change should i change the pads

[jonjoe]

so im going to change the front rotor on my car during the week should i change the pads aswell i only change them about 4 weeks back.im sure one of my rotors is warped in the front would it be ok to still use the pads because they were changed only a few weeks back or would it be dangers to put them back on?

[Zembonez]

Typically I would not reuse brake pads... but if you really just put them on, I'd sand the face on a nice flat surface using some 80 grit to remove the residue and reuse them.

[johnoh]

Originally Posted by Zembonez

Typically I would not reuse brake pads... but if you really just put them on, I'd sand the face on a nice flat surface using some 80 grit to remove the residue and reuse them.

ditto what he said.

the pads will work fine - the only risk is squealing, so just make sure the pad surfaces are perfectly flat. If the old rotors dug into them unevenly such that you can't sand them to be flat again, they may make noise even with new rotors.

[silver04rollas]

You might have to. That is what Toyota did in my case. The reason is, once the disks need to be replaced, the brake pad wear shape changes according to the wear on the disk. Once you put brand new disks with full thickness on the disks, it will not work properly with worn out and thin brake pads.

[MasterTecInSTL]

I never bought that. Yes, reusing pads might take longer to "seat" to the rotor but it will still happen. Just don't be surprised if there is noise and decreased braking ability for about 20-50 miles or so.

It would be very difficult for me to justify purchasing new pads to replace ones that are only a month old. If it were me I'd just be reusing the old ones.

Besides it's not THAT difficult to replace them again if need be.. just pull the wheels and one bolt to swap pads out.

[jonjoe]

thanks guys well this seems a 50/50 on weather to change the pads i think the best thing to do would probably just to change them i know i wasted a set of pads but its better to be safe than sorry when theres kids going to be in the car.

[boberic]

Originally Posted by jonjoe

thanks guys well this seems a 50/50 on weather to change the pads i think the best thing to do would probably just to change them i know i wasted a set of pads but its better to be safe than sorry when theres kids going to be in the car.

First, this isn't a safety issue.

If a rotor is warped, you can replace just that one rotor. If the pad isn't "scraping" the surface evenly but instead is giving you an area of rust on the rotor matching up with a groove in the pad, then you'd want to flatten the pad before putting it back on or replace it.

In my experience, once you get an area where the pad isn't wearing down the rotor you'll have rust there which is much more abrasive than the original metal so it wears the pad out in that area very quickly rather than other parts of the pad.

Also, if just one rotor is vibrating and you're sure which one then there is no good reason to replace the other one. Since this stuff is hydraulically actuated and self adjusting (instead of cable or linkage actuated) you really don't have to match up thickness side to side. What should match up is overall grippiness but imho the tire grippiness is much less than whatever pad/rotor combo you have, so it's rather unlikely that you'll have one side sliding and the other side locking up due to different pads/rotors, unless you do something stupid like put racing pads/rotors on one side and cheapo organic on the other. Even then, if you have ABS you're probably not going to notice anything mixing that stuff up.