Disc warping

ready to replace the 4th set of rotors on my 2012 4 runner. switched to tundra rotors on recommendation from a member a couple of years ago. They lasted a while but not even till the pads are worn out. 60K miles on the car. sick of replacing rotors. any new recommnedations?

 

Are you bedding in (burnishing) the rotors and pads when you swap them?

 

not sure what you mean by bedding the pads. i am a professional mechanic for 50 years. i told my customers and practice it myself that you do not hall butt and slam on the brakes to "seat them" you must use the brakes gently to gradually heat them up and "seat them in"

 

Doing something wrong i have not had any issues.

 

https://www.wagnerbrake.com/technical/technical-tips/break-in.html

 

rocko exactly the procedure i have always followed and told my customers to follow. also when i was the foreman of a very large fleet of trucks,vans i told the drivers to avoid panic stops and hard braking from high speeds for several cycles brakeing.

 

I agree. What pads are you using?

 

If you google the situation there are many many people with the same problem going back several years with 4runners. that is where i read that one solution is to go with tundra rotors. seemed to be fine for about 2 years and as i said pads are only 1/2 worn but rotors are warped again. i am not hard on my brakes. also have a dangerous hesitation that you can google and find many many comments on that situation.

 

to tell you the truth since it has bee probably (i will check my notebook) 2 years i do not remember the brand. i think they are oem but will not swear to it.

 

5th gen rotors aren't warp prone as 4th gen were. Double check lug nuts torque after each tire rotation.

 

have always used a torque wrench to torque wheels on my 4 runner, f350CC, 75 vw super beetle, 91 volvo 240. never use an impact except to spin the nuts down to save time

 

How's the rotor thickness? Is one side wearing down more/less than the other? Can you verify that all your pistons retract and extend freely?

 

I would veryify pistons are not sticking. Get new rotors or resurface at a shop you trust, then try another brand-Akebono possibly.

 

If they're warped, it's usually the case where you won't be able to turn the rotor down and still meet the min thickness requirement since you have to turn enough material (min material cleanup) to remove the warping. Turning rotors isn't done as much these days, but you want to start with rotors that are straight and not worn odd. You're really just trying to remove the surface that you bed in from depositing the previous pad material onto so you can re-bed with the new pads on a fresh metal surface.

 

People say warped. Most of the time it's uneven pad material transfer. It's the OPs choice. New or resurfaced. Either way I doubt much rotor material was used up in 15k miles.

 

Agree. The only time I've seen badly warped rotors is on people's rigs who are brake slammers. Just put way too much heat into them all the time. I've personally had the unfortunate event (on my truck) where stuck pistons caused one side of the rotor to wear down thin on the backside compared to the frontside. Glad I caught that one in time.

 

Yeah, as I understand it, it's just about impossible to get rotors to truly warp aside from getting them glowing red.

 

I will give you some things to look at:

Do the rotors have a manufacturing defect, doesn't matter the brand

Are your calipers screwed up, sticking

Are your brake pads the wrong material for the rotors you are using

Start with those items.

 

This. I have seen new Centric and Wagner rotors that were out of round when new.

 

Maybe your pads are too aggressive? Are you using ceramic or semi metallic?

Can also try StopTech or Raybestos slotted rotors which will scrape away pad material and prevent uneven buildup.

 

This. Your rotors are not warping for no reason - if that's really what's happening. Sticking pistons causing the pad to ride the rotor will do that. Get a simple, and cheap, magnetic dial indicator off Amazon and see what the rotors show.

 

Mind elaborating on this?
Haven't heard of any brake pad material being "wrong" for the rotors, since all rotors are made primarily with the same materials.

 

I agree that all rotors made from same material, and in most cases from steel (sometimes from fiberglass). When I choose steel, I prefer "Made in Japan" steel.

 

I've not seen a fiberglass rotor. Last thing I want is my braking system to catastrophically fail. Seeing how the failure modes are similar to carbon, no thanks.

Also, steel "made in Japan" isn't really anything special. It's a buzz phrase for selling kitchen knives.

Steel used aerospace, vehicles, and other certain industries is certed and required to meet particular specifications. If it meets those, it doesn't matter where it comes from... Unless of course your country isn't allowed to purchase raw material from certain areas of the world

 

It could be the pad material, semi met, ceramic some may not play as well as others

 

Yes validity to this. And is my experience I have had no issues on my 4Runner even when I tow. My father had a 94 Dodge Spirit he easily put 60000 Km on a set of quality brake pads. He gave the car to my teenage son as a first vehicle who would then proceed to burn out the pads and rotors in less than 20000 KM constantly. It wasn't the car it was his driving whether 2 foot driving or aggressive braking. As a auto mechanic I always never let him make excuses. If your brakes work as designed and are maintained properly the rest boils down to your driving full stop.

 

No.

 

Yes