When to change the brake rotors

[nglayton]

New OEM rotors are $58..... Why screw around? Just get new ones when you change the pads. You're talking once every 75k miles roughly.

Well, I guess that depends on how you define "screw around".

I would define screwing around as spending an extra $58x4= $232 when it's not needed, as screwing around.

5 Tanks of gas, 4 decent dinners out with my wife, etc, etc.
I can think of all sorts of things to do with the $$$.

 

[00Sebby]

Well, I guess that depends on how you define "screw around".

I would define screwing around as spending an extra $58x4= $232 when it's not needed, as screwing around.

5 Tanks of gas, 4 decent dinners out with my wife, etc, etc.
I can think of all sorts of things to do with the $$$.

You should do it because it makes the people who don't mind throwing money at non-problems and paying for that "insurance" feel better that they are not the only ones wasting money. My Trail has over 130k miles on it with original rotors. No vibration or anything, so why would I spend the $200+ for new rotors?

 

[nglayton]

My Trail has over 130k miles on it with original rotors. No vibration or anything, so why would I spend the $200+ for new rotors?

Another vote for not changing them.......

 

[enapa]

Well, I guess that depends on how you define "screw around".

I would define screwing around as spending an extra $58x4= $232 when it's not needed, as screwing around.

5 Tanks of gas, 4 decent dinners out with my wife, etc, etc.
I can think of all sorts of things to do with the $$$.

Ok well if you would like to save $100 and spend a whole day waiting for rotors to be turned on a $40k rig then I guess that's your choice.

 

[Badmeat]

Unless I have vibration under braking due to pad imprinting or warping, I have never changed the rotors. Given that my last 4Runner had some pedal feedback, I did change the front rotors and pads to alleviate that. I did the rear rotors once the pads were completely gone, so it was necessary.

I’ve never been a fan of the thought behind resurfacing rotors. It’s often not much more expensive to just buy new rotors. Plus, since you’re removing material from the rotor, wouldn’t it be easier to reach temps where warping could occur?

 

[00Sebby]

Unless I have vibration under braking due to pad imprinting or warping, I have never changed the rotors. Given that my last 4Runner had some pedal feedback, I did change the front rotors and pads to alleviate that. I did the rear rotors once the pads were completely gone, so it was necessary.

I’ve never been a fan of the thought behind resurfacing rotors. It’s often not much more expensive to just buy new rotors. Plus, since you’re removing material from the rotor, wouldn’t it be easier to reach temps where warping could occur?

Same here. If everything is smooth and vibration free I never change the rotors. If they are warped, resurfacing only removes the "high" spots on both sides of the rotor. This creates variance in the material thickness of each surface which will lead to more warping if they get too hot. Therefore, they do get replaced if warped.

 

[nevada]

all day getting rotors resurfaced? the process maybe takes an hour.

and as to warping, they typically don't. true, the thinner they get, the less they are able to properly dissipate the heat, but warping is generally not a concern.
done correctly, resurfacing the rotors removes very little material.

 

[arthurm]

My last two checkups showed this on the pads, all on original rotors:

mileage: 36292
LF: 10mm
RF: 10mm
LR: 9mm
RR: 9mm

mileage: 41400
LF: 8mm
RF: 8mm
LR: 4mm
RR: 4mm

The rear rotors have the slightest lip all around. Fronts and rears have very slight grooves. I mean, they're not perfectly smooth but I don't expect them to be.

Should I be concerned about the big drop in the rear pads?
Can I replace just the rear pads or must I do all four wheels?

 

[nevada]

My last two checkups showed this on the pads, all on original rotors:

mileage: 36292
LF: 10mm
RF: 10mm
LR: 9mm
RR: 9mm

mileage: 41400
LF: 8mm
RF: 8mm
LR: 4mm
RR: 4mm

The rear rotors have the slightest lip all around. Fronts and rears have very slight grooves. I mean, they're not perfectly smooth but I don't expect them to be.

Should I be concerned about the big drop in the rear pads?
Can I replace just the rear pads or must I do all four wheels?

you can do just the rears.

 

[sm4r]

It partially depends on how long you plan to keep your 4Runner.

I just changed out my pads and rotors for the first time at 80K miles. Didn’t get exact measurements but the rotors looked fine front and rear.

I probably could have machined them quite easily but zero chance I’d feel comfortable running the original rotors up to 160K miles when the pads are likely to need replacing again.

My thinking was why do...
80K - Replace Pads / Machine Rotors
120K - Replace Pads and Rotors (can’t see going beyond 120K miles on stock rotors, and you’ll want to replace the pads while you’re in there)
200K - Replace Pads / Machine Rotors
260K - Replace Pads and Rotors
= 4 Services, 16 Pads, 8 Rotors

Easier to just do...
80K - Replace Rotors and Pads
160K - Replace Rotors and Pads
240K - Replace Rotors and Pads
= 3 Sevices, 12 Rotors, 12 Pads

Is paying for 1 extra servicing and 4 additional brake pads (2 sets) really worth 2 sets of rotors (and 20K miles)?