Rear Rotors: Turn or Not?

[ebod]

At my last inspection (30k mi on 2004 LC), I was notified that my rear pads were getting low and that I should soon get new pads and turn the rotors. That was a couple of months ago. I've now got a squeak while driving so I think its probably time to do the brakes.

My question is whether I should just get new pads ($110, at the dealer) or whether I should also have the rotors turned ($289) (of course, dealer will recommend turning).

I've heard that turning the rotors is often a waste and can lead to warped rotors soon after. Thus, I'm inclined to just do the pads and put new rotors on next time I need brakes. That said, if it's a safety issue or if I won't lose the squeak without turning the rotors, I'll turn them.

What are the downsides to not turning rotors? If it's just shorter pad life, then, unless it cuts the pad life in half, it seems like I ought not turn.

Thanks in advance for your suggestions.

 

[SINCITY100]

IMO, if no vibration is present prior to replacing the pads, and the rotors` surfaces are smooth ( but not glossy) and groove-free, I would leave them alone.

I dont remember the last time I actually turned a rotor on one of my Toyotas (although I tend to change pads "early" on my vehicles ) and therefore have been able to stretch the life of the rotors substantially If I am wrong, I guess I am just lucky cause the new pads have always seated nicely, and seemed to last as long as they would`ve if I had turned the rotors.

 

[spressomon]

IMO, if no vibration is present prior to replacing the pads, and the rotors` surfaces are smooth ( but not glossy) and groove-free, I would leave them alone.

I dont remember the last time I actually turned a rotor on one of my Toyotas (although I tend to change pads "early" on my vehicles ) and therefore have been able to stretch the life of the rotors substantially If I am wrong, I guess I am just lucky cause the new pads have always seated nicely, and seemed to last as long as they would`ve if I had turned the rotors.

That's the way I proceed too. Thicker pad = more heat absorbing capabilitiy...so your strategy to replace pads when they have more material seems to make sense.

 

[SINCITY100]

That's the way I proceed too. Thicker pad = more heat absorbing capabilitiy...so your strategy to replace pads when they have more material seems to make sense.

Yes, thats my theory anyway

It seems as though the pads "feel" different as they wear, especially on the thinner side ( 20% or less ) with more fade and noise too.. So I`ll usually try to throw a new set on when there is around 40% or so material left .

Sure, it might be a bit of a waste to toss away pads so early, but its proven to work for me... especially considering my driving habits ( besides, I have a connection in Toyota parts )

 

[Jim_Chow]

Replace, don't turn. If you turn rotors, they'll just warp sooner due to reduced metal thickness.

 

[spressomon]

Yes, thats my theory anyway

It seems as though the pads "feel" different as they wear, especially on the thinner side ( 20% or less ) with more fade and noise too.. So I`ll usually try to throw a new set on when there is around 40% or so material left .

Sure, it might be a bit of a waste to toss away pads so early, but its proven to work for me... especially considering my driving habits ( besides, I have a connection in Toyota parts )

Not to hijack this thread...but I finally saw your pics from your 700+ mile adventure! Looked like great fun!

 

[NMuzj100]

I had a rear rotor turned when I let the rear pad get metal to metal. They took 1mm off the rotor and the minimum spec is 16mm I still had 17mm after turning. This means they took ~6% of the material thickness. I doubt you will have any warpage or heat related problems after turning if it is needed (as long as you stay above minimum). I would turn for any roughness or grooves but not as a routine.

If you have a queak now and you don't turn then you will likely have a squeak when you are done. This is why the dealers and brake places machine rotors routinely. Fewer come-backs for noise and roughness until the pads conform to the rotor.

I don't think you'll get reduced pad life for not turning but you may get noise and roughness until they wear to "match" if you have a rough rotor.

Mine cost $14 to turn so I would not pay the dealer $200 to do it.

For brake ?s I have found these Technical Papers from Stoptech informative.

 

[SINCITY100]

Not to hijack this thread...but I finally saw your pics from your 700+ mile adventure! Looked like great fun!

Thanks ! It was a blast, Just me, the open desert, a 120QT cooler full of beer, and my trusty UZJ... Trust me, It doesnt get ANY better than that !


Oh..Back on the subject

I wonder how much the heat transfer properties and performance actually change as the rotors get thinner ? I bet its more than one would expect

 

[ShottsUZJ100]

My question is whether I should just get new pads ($110, at the dealer) or whether I should also have the rotors turned ($289) (of course, dealer will recommend turning).

The prices are wacked. I pay something like $40-50 for Toyota pads. Cost to turn rotors is something like $25/set. The rear rotors come off easy.

I turned all my rotors twice and replaced them the 3rd time at about 100K.

 

[SINCITY100]

Oh.. I thought the $110 was WITH labor, if not.. you really DO need to shop around for those pads mister

 

[ebod]

Thanks for input.

The prices in my question were parts and labor (from the dealer). I'm sure I could find better prices elsewhere, but the dealer is walking distance from my office.

 

[ShottsUZJ100]

Thanks for input.

The prices in my question were parts and labor (from the dealer). I'm sure I could find better prices elsewhere, but the dealer is walking distance from my office.

You can save $248 by having the dealer hand you your rotors and you take them to PepBoys and return (less the feeof $25 to turn them). Or, for about $248 you can buy NEW Toyota rotors.

 

[Tinkerer]

You can save $248 by having the dealer hand you your rotors and you take them to PepBoys and return (less the feeof $25 to turn them). Or, for about $248 you can buy NEW Toyota rotors.

Everybody has their own take on this perennial question.

My .02, based on experience with many brake jobs (not just my own) plus additional training & industry experience:

I'll never turn another rotor again. Well-made rotors (such as Toyota's) are hardened and ground from the factory, with carefully controlled metallurgy & surface conditions and resulting pad-rotor tribology. "Turning" a rotor at a local shop means putting it on a ragged-out lathe with variously worn & dulled tooling, incorrectly adjusted, with "anybody's guess" speeds & feeds, usually resulting in one screwed up rotor that will overheat, eat pads, and warp. This is all without even considering the degraded thermal and mechanical properties resulting from thinning the rotor by turning it (despite the OEM "minimum turn thickness specs), another factor adding to tendency to warp.

If my pads are worn, I replace with new OEM pads and rotors.

I no longer have time & money to waste redoing brake jobs that fail because of turned rotors. (Remember, if the turned or reused rotor causes problems with new pads, the new pads really should be replaced again with a replacement rotor, so such failure also adds the cost of another set of pads.)

But, as noted, everyone has a different view of this subject.

AFAIC, the 100 Series is such a great vehicle with excellent brakes, that I will not spoil it by attempting to save a few bucks on a brake job, leading to sub-par braking performance.

Oh - and the $289 will buy brand new OEM rotors, and leave almost enough change to buy new OEM pads too, at my local stealer.

 

[EdsCruisin]

Rotors warp when we least expect it, like when the idiot up the road decides to stop and turn left at the last minute and causes everybody to test their ABS. If you can't feel any throbbing at all I would pass on the turning, but even the slightest throb means they are warped, and if you tow a trailer that becomes dangerous.

Whatever you do, I would never take them to a place like Pep Boys or any other auto repair shop. Find a machine shop that does all type of work for dealers and quality repair shops. Those guys are in the machining business and maintain their equipment better. They also do machining all day = real experts. My local shop charges $15 per rotor, which is worth every penny.

 

[NMuzj100]

Whatever you do, I would never take them to a place like Pep Boys or any other auto repair shop. Find a machine shop that does all type of work for dealers and quality repair shops. Those guys are in the machining business and maintain their equipment better. They also do machining all day = real experts.

+1 - Take it to a place that specializes in machining. Not a "We do it all! parts and mufflers shop."

To stir the pot a little more ...

Give this article a read - The "Warped" Brake Disc and Other Myths of the Braking System

 

[LXPearl]

I only turn rotors if there is unusual wear on them and use OEM pads. I finally had to turn one of my rotors on my 94 Previa after 180K miles, but made the mistake of going to a local auto store. Within 15K miles the rotor was scored and I had uneven braking, so I took it to Toyota and they did a great smooth job on turning the rotor. The new oem pads and dealer turned rotor have over 30K miles on them and still give nice even and smooth stops.

 

[1loudLX]

The past 3 times I've replaced my brakes I've gotten new rotors too. Usually they end up getting warped and since the front rotors are already off, i just get new ones put on.

The back also, since the wheels are off and rotors are off i just replace them. I just feel that, its my brakes...I'd rather have all new stuff in then just replace one part and "possibly" reduce performance.

 

[SINCITY100]

The past 3 times I've replaced my brakes I've gotten new rotors too. Usually they end up getting warped and since the front rotors are already off, i just get new ones put on.

The back also, since the wheels are off and rotors are off i just replace them. I just feel that, its my brakes...I'd rather have all new stuff in then just replace one part and "possibly" reduce performance.

Ummm... Could I have all your "old" brake stuff ? .... I LOVE brake hand-me-downs

 

[spressomon]

Ummm... Could I have all your "old" brake stuff ? .... I LOVE brake hand-me-downs

I still have my 4-rotors if you want them...come and get 'em

 

[SINCITY100]

I still have my 4-rotors if you want them...come and get 'em

Sounds good, I`ll take em` !

But `ya better line up a good trail to run with me while I`m there, I dont get up North very often