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Discussion Starter #1 (Edited)
Does anyone know of any disadvantages to running stock rotors that are slightly (<=1mm) thinner than the FSM miniumum spec? The rotors are fine, no warping or grooving, since I replaced my pads well before they were completely worn. I'd rather wait to buy new rotors so I can upgrade some other things first. Thanks...BTW, the car is my daily driver (a whole 3mi to school!) and I don't plan on taking it to the track anytime soon.
 

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my stock original pads and rotors lated about 60K miles. when it was time to replace I had to do all 4 rotors and all sets of pads at the same time.....never turned or anything, our stock OEM stuff works very well.....
 

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they cannot dissipate heat as well and they warp under hard driving.

Just chub the $$ and get a set, they aren't that much $.
 

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Discussion Starter #5
98mkiv said:
they cannot dissipate heat as well and they warp under hard driving.

Just chub the $$ and get a set, they aren't that much $.
It is when you live on a grad student stipend!

Ok, so 2nd question, I replaced my pads ~10k miles ago. Will putting new rotors on now cause problems without replacing the pads. I figure as long as I go easy on the brakes for a while, the pads should conform to the new rotors pretty well...
 

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I don't know. It depends how rough they are. Usually new rotors get new pads. Cut rotors are rougher and they cut the glazing off the old pads, I don't think that will happen with new rotors, they are too smooth. You will likely have problems doing this.

I would recommend new pads to go with the new rotors.

Also, if you have warped rotors now, you should look to why. Sometimes it is just a gummy slide, but more often than not, you have a stuck caliper and need to either rebuild your calipers ($40 to have it done) or replace them with rebuilt (good luck finding this) or new (good luck affording this).

Congrats on being a grad student. Now stop crying poor.
 

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Brakes=safety. Why skim out on such an important aspect of your car and your safety. Just get it done.
 

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Discussion Starter #8
PsyKotiC RydeR said:
Brakes=safety. Why skim out on such an important aspect of your car and your safety. Just get it done.
I def. agree... I was just having a hard time understanding why a slightly thinner rotor would immediatly become unusable. (I am not in the buisness of romping around, slamming on my brakes all the time.) The reason why the rotors weren't replaced initially is because I didn't think that they were going to be so close to the minimum spec. when I replaced the pads so I didn't buy new rotors. Now, it appears that I have to buy new pads again :doh:

Can anyone else comment on using slightly used pads on new rotors. The pads only have 10k miles, which means they are only 10-15% worn at most. Could I sand the pad to remove this glaze as 98mkiv pointed out?
 

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"Can anyone else comment on using slightly used pads on new rotors. The pads only have 10k miles, which means they are only 10-15% worn at most."

There's nothing wrong with using used pads with new rotors or vice versa. You will probably get some vibration and "grabbing" for the first few miles, until the pads "seat." The pads and rotors will eventually mesh and you'll be good to go.
 

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rotors have a minimum thickness for two reasons:

The brake system is designed to accomodate worn pads and thin rotors, meaning the piston can only extend so far. You don't need to worry about this, though you could damage your calipers if you run worn pads on an 1mm (.040") too thin rotor. As your pads get thin, which they will, you will ruin your caliper pistons and bores.

the rotors have a certain heat capacity and tend to warp quickly when you dump too much energy (heat) into them. The thinner they are, the less heat capacity they have and the sooner they warp.



-M
 

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97TT6SP said:
It is when you live on a grad student stipend!

Ok, so 2nd question, I replaced my pads ~10k miles ago. Will putting new rotors on now cause problems without replacing the pads. I figure as long as I go easy on the brakes for a while, the pads should conform to the new rotors pretty well...
Umm - if you can afford the car, you can afford good brakes.
And just break in the new rotors with the slightly used pads. Should be no problem.
 

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Discussion Starter #13
Thanks everyone for replying. It looks like my suspension upgrade is going to have to wait a while :( Anyone want to trade a new set of Tein's for my flux capacitor? It makes time travel possible you know...
 
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