macgiver wrote: ↑
Mon Aug 30, 2021 2:14 pm
p.s. Just seen your experience with your beloved dog , we had Jack Russell w/ baseball tumor on jaw and feel your pain - we do everything for our little ones - God knows you did.
Appreciate the good wishes very much. Funny how ours brains hang onto the littlest things. Every morning when the alarm goes off, the back of my brain insists on doing a double-take when the foot of the bed is empty. I wonder how long it will be before my hindbrain gives up. I'm thinking it'll take awhile.
GM is right, if it ain't broke then don't fix it. Whether you ever get warpage depends greatly on the quality of the rotor casting and the metallurgy, but also on the individual flaws in a given casting. Castings all have flaws just like diamonds, it's a matter of how hard you have to look to find them. There's no such thing as a flawless one, and whether they cause problems depends on where and how big they are. They also have carbon nodules just like an engine block, and once the nodules are reduced to powder, if it hasn't already warped then it never will. My deceased hoopty Hyundai went through about 6 sets of front pads and never had any warpage at all. There was no point in cutting them so I never did. We cut fronts routinely at the shop, but probably 90% of the people who come in with a brake complaint already have some shudder. We only ever cut rear discs or drums if there's an issue. When fronts get cut, I'd say probably 8~10% will be shuddering again inside of 10K miles, and that means a serious flaw that's distorting under heat stress. It will only get worse as more metal is removed, so cutting them again is pointless, they have to be replaced.
Back to the topic, every brake "expert" I ever talked to told me you can't resurface D&S rotors because the bits will jump at the far edge of the hole or slot and the resulting ridge will striate the pads and cause premature wear. I can now tell you definitively that the "experts" were full of baloney. My month-old pads are flat as pancakes and don't show the slightest evidence of any problems. I can only assume the ridging they talked about was an artifact of trying to take off too much metal and finish the cut quickly.