Acura RSX, ILX and Honda EP3 Forum banner

Do you have to change both brake pads at once?

9K views 17 replies 8 participants last post by  davidluko 
#1 ·
Question... (might be a stupid one)

I had a little accident and shattered my rotor which messed my one driver front brake pad up.

The pads (OEM from Acura) were almost new and the passenger side is still good. Can I find another used driver OEM pad or should I change both at the same time to match the wear? (This is in an Integra but honda-tech was being retarded so I thought I'd ask here)
 
#5 ·
You actually normally buy them in sets of two (front or rears), not four. Fronts obviously wear much faster.

But I'm asking because my passenger side is almost new (a few months old) and I have driver-side pads that came with the suspension that I'm putting in my car to replace the bent stuff. I figured it would work until whichever pads are more worn wear out, then replace both at the same time... unless it'll affect brake bias/feel/etc. I can get new OEM pads for $45, so it's not a matter of money. Just laziness and curiosity. I'm wondering if anybody has done it before.
 
#9 ·
Ok idk who in there right mind replaces all 4 brake pads and rotors at once (btw turning rotors is the stupidest idea ever and actually makes it worse then better). You're front pads might last 40k, if you're gentle. Mine probably last 20k cuz i drive hard and do track days as well. The rears on my car last 80k miles. Ive never even replaced my rear rotors yet and im at 152k.

Buy a set of pads on tirerack for 30$, there awesome pads ive used em for 5yrs now. Change all 4 front pads its easy as hell, if you shattered one of your rotors then replace both em so you don't get uneven wear and what not. Brakes and tires are the one thing you can't get lazy with, your life kinda depends on that.
 
#10 ·
I agree that there's no point in changing all the pads at once because the rears wear much slower but how does turning rotors make them worse? If they're warped or scratched then turning them makes the surface perfect again.

What I ended up doing is using my original OEM pads on the front right side and the used OEM pads on the front left side because they're both similar wear/almost new. And I also changed both rears with new OEM pads because I noticed they were wearing down while I was working back there. Not sure if I'll be needing to replace/resurface my front left rotor, the used one that I put in, because I haven't gotten the car running yet.
 
#11 ·
Think about it, the reason the rsx has a 1.1in thick rotor is to disperse heat better. If you make it thinner its going to disperse heat worse then before, its a matter of time before it warps or scratches again.

For example. I think my powerslot rotors have close to 80k on em, if not more, there not warped or scratched but they are worn. I wouldn't think about cutting em, id rather spend the 120$ to buy a new rotor then (well its free for me since i have a machine at work) then to spend time cutting em or money cutting em and have to do it again in 20k miles instead of not worrying for another 80k.

But then again this is personal preference.
 
#12 ·
Oh well I highly doubt the probably less than 1 millimeter will make a difference. It's just speculation from both of us. I prefer to get new rotors though because resurfacing doesn't always get the hot spots out from hard braking (which is what usually warps them in the first place).
 
#13 ·
Well think about it its not just 1mm, might be more depending on the condition of it, and its 1mm all the way around. I cut rotors you'd be surprised how much metal actually comes off just cutting one. And i've seen so many of em come back warped again. I drive hard on my brakes i see no point in cutting. I replace my pads more then likely once a yr thats how hard.
 
#14 ·
But the main surface of the rotor (where the brake pads touch) isn't affected, it's just the very tiny bit (like I said, probably less than or about 1 millimeter) all the way around the edge that'll matter because that's the only surface area that you'll be losing.
 
#15 ·
You're losing the surface area as well thats the part your cutting. The machine starts closer to the studs then cuts all the way around till the edge, usually the part that has a little lip. You're not losing surface area but that doesnt matter, the the thickess that you're losing. Its the thickness that disperses the heat.
 
#16 ·
How does thickness disperse the heat? I'll admit I don't know a lot about that stuff, but I figure it's the surface area that matters the most to take the heat away (reason for vented rims back in the day before they were common, and air ducts to the brakes).
 
#17 ·
Thickness and size disperse the heat. Think of it this way. Heat up a piece of aluminum 1x1x1in, then heat up a piece of aluminum 2x2x2in and see which one cools faster. The thicker the rotor the more area the heat has to go. If the heat cant travel anymore it will stay where it heats up the most and thats the surface. If your rotor was only an inch or so thick, you'd break hard a couple times and it would be red hot. Its its 3in or thicker then you have more aluminum to heat up and it wouldn't get hot as quickly.

Idk if that made any sense but thats the best i can explain it, the rotor just doesnt get hot on the surface, it goes red hot all the way thru.
 
#18 ·
Hmm I guess that makes sense if you think of it on a bigger scale.. but i don't know how much a millimeter would matter. Plus, with prolonged heat like during driving i'm sure it heats fully all the way through so that the thickness won't matter anymore. It's the air blowing past that is what really matters.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top