4th Gen Warped Rotors

[dmanla]

At 20K miles, my rotors ('04 SE 4x4) were warped (all four of them). My dealer checked them out and recommended replacing all four rotors and pads. The good news was that they did it under warranty.

I also had them rotate and re-balance the tires. The dealer has the Hunter balancing system. The tires were out of balance as well. Anyway, I got the truck back today and it feels nice and smooth again.

One thing I do want to gripe about is the lug nut torque was very uneven all around. I had to loosen and re-torque (to 83 ft-lb) every nut.

Overall, I'm pretty satisfied but still suspicious of why the rotors would warp so quickly or at all.

 

[starflt]

Rear Rotors

I took my 4R to Midas the other day for a free inspection. Just having had the fronts done, the pads and rotors were fine, but I still experience the surging and pedal vibration. They found runout on the rear rotors of .004" on one and .006" on the other. The pads have tons of meat left. Those runouts don't sound like a lot. Is that enough to cause the surging and pulsation?

 

[RickyCRX]

I doubt it...

The calipers are designed to float a little to compensate for things like that...


Maybe this feeling has something to do with the dynamic brake force distribution system?? Maybe the master cylinder/proportioning valves are automatically adjusting as you slow down and the vehicle weight transfer changes??

Ricky

 

[starflt]

??????

I doubt it...

The calipers are designed to float a little to compensate for things like that...


Maybe this feeling has something to do with the dynamic brake force distribution system?? Maybe the master cylinder/proportioning valves are automatically adjusting as you slow down and the vehicle weight transfer changes??

Ricky

You lost me. I'm not a gear head, and the vehicle never acted this way before. Can you please put this into language I would understand?

 

[RickyCRX]

Look up "Toyota EBD" (Electronic Brake-force Distribution) and do some reading; it's a feature on all of our 4th gen 4Runners:

"EBD regulates the braking force applied to each wheel depending on road conditions, for example, a wheel on a dry surface will receive more braking force than one on a slippery surface."

Maybe the constant adjusting of the system is what we are feeling?????

Ricky

 

[starflt]

EBD

Look up "Toyota EBD" (Electronic Brake-force Distribution) and do some reading; it's a feature on all of our 4th gen 4Runners:

"EBD regulates the braking force applied to each wheel depending on road conditions, for example, a wheel on a dry surface will receive more braking force than one on a slippery surface."

Maybe the constant adjusting of the system is what we are feeling?????

Ricky

OK, thanks. I will research it. However, this is a new feeling. The truck used to stop smooth as butter. I've had this truck for more than 3 years and this is a recent development. Getting the front pads and rotors replaced helped, but didn't eliminate it. The only other likely variable I've been pointed to is the rear rotors, which have moderate run out.

 

[RickyCRX]

I wouldn't consider a few THOUSANDTHS of an inch to be "moderate" by any stretch of the imagination.

Of you want to turn the rear rotors, go ahead and try it...I just don't think that's the problem.

Ricky

 

[Ghostface80]

Re: Front Brakes..Looking for Answers

I have an '03 SR5 V8 with 27,500 miles that mostly sees around town driving. Around 21000 miles, the front brakes started to squeak and the brake pedal pulsed. I had new ceramic pads and aftermarket rotors put on. Immediately after, I would feel the vehicle surging, or limping to a stop, and the pedal still pusled. It got worse and after reading a lot of the posts in this forum about problems with aftermarket parts, I had my mechanic put Toyota rotors on the truck. I kept the ceramic pads on.
The aftermarket rotors had warped and had a runout of .022. The new OEM rotors have improved the situation, but I still experience the surging/pusling, especially when the truck has been driven for a period and is warmed up. This is especially true when braking on an off-ramp coming off the expressway. The surging is completely absent when the truck is cold like first thing in the morning.
The vehicle rides out straight and true without a hint of vibration at all speeds. It's only when I press the brake pedal that I feel the surging/pedal pusle.
Anyone have any ideas what I may be missing? My mechanic did a runout check on the front wheel hubs and one measured .002 and the other at .004. That doesn't sound very significant, does it?
Thanks for your help.

I have the EXACT same problem. I also started a thread under 'general discussions' a few days ago. I'm thinking it could possibly be something faulty in the master cylinder. Hope you can figure out what the problem is.. I'll keep you updated if I find the culprit also.

 

[starflt]

Re: Re: Front Brakes..Looking for Answers

I have the EXACT same problem. I also started a thread under 'general discussions' a few days ago. I'm thinking it could possibly be something faulty in the master cylinder. Hope you can figure out what the problem is.. I'll keep you updated if I find the culprit also.

Thanks GF. Any information would be welcome. I saw your thread in general discussions. Hopefully it will yield some help. I thought perviously about the master brake cylinder, but, my pulsation/surging problem definitely varies with wheel speed. I would think that would rule out the master, wouldn't it?
I am having the rear rotors replaced this week, and will report the results. I've got my own mechanic on the case. He's doing the work. If this doesn't solve the problem, we'll take the truck out for a drive while he has his hand-held computer plugged into the interface and see if he can determine what the brakes are doing.
By the way, my pedal stays firm under pressure.

 

[M1911]

I just had to replace the front rotors on my 2003 4Runner. But seeing as I got ~47,000 miles out of them, I'm not complaining.

 

[starflt]

New Brakes

Well folks, I had my rear rotors and pads replaced yesterday. At this point, I can tell you that the pedal pulse and shuffling to a stop is totally gone. My Runner stops like it did when it was brand new. My mechanic was amazed that the slight runout readings he had seen on my rear rotors would have caused that condition. The only conclusion he can draw is that these trucks are produced very tightly. I guess that's not all bad. In the 3-1/4 years I have had mine, I can say it has been great. So, if I have to have a complete brake job every 25000 miles or so, that's the price of owning a vehicle of this caliber.

 

[dwulffusa]

I am at 37k, alot of highway but brake pretty hard and for the last couple of months the brakes (i think) have developed a shudder (more like a surge) coming to a stop or when warm in stop start driving. I say 'i think' because I experimented putting in neutral coming to a stop and that results in a much smoother stop, could it perhaps be a transmission downshift issue?
I havn't had it checked out yet but am suspecting slightly warped rotors, but then wouldnt it shudder all the time?

Anyone done a brake pad upgrade? Anything out there that will give a more positive feel?. I have bitched about brake assist before and I know its a love it or hate it thing, I hate it because I would like to control the stopping force with the pressure of my foot, not the speed with which I touch the pedal and would like the same response from the same pressure everytime which is not the case. I guess it also has to do with the condition of the tires, and my stock dumflops are close to done, I was really trying to hand over $800 for Revo's this week but no-one had them in my area and they all said I had to wait a week so I got annoyed and didn't order them!

 

[greasefingers]

The run-out spec for the disc is 0.05mm (0.0020in) This is tighter than a ducks a_s!!!

This would also mean that having them turned at a local shop is taking a chance, as some may be able to get this within spec but many will not.

 

[gizmopt2002]

I don't mean to hijack the thread, but my brakes are in need of replacing and I was wondering where you guys have gone and how much was it? Thanks.

 

[greasefingers]

You are not actually hyjacking as the older the 4th gens become, the more and more this topic will surface.

I would only buy dealer pads!! Hands down one of the best.
The rotors is a different story. I am waiting for Brembo to make them for the Sport runner (larger discs) but if you have the smaller ones then there is your answer.

 

[RickyCRX]

Are there any pads that have a better (higher) heat range than stock? There have been some times I've noticed during very agressive driving (or a hard stop or two in heavy traffic while towing) where the brakes seem to start to reach a point of minor pad fade. I usually can detect it quickly and back off from using the brakes so much, but it's unnerving that a couple of hard stops from highway speeds is enough to get the pads to start fading a little bit, and that's with the larger Sport's 13.2" front rotors, too.

Ricky

 

[greasefingers]

I have not yet looked into aftermarket pads, but people say that Hawk is one of the best.

Maybe the Tundra folks can assist you with your search?

 

[toybox]

You are not actually hyjacking as the older the 4th gens become, the more and more this topic will surface.

I would only buy dealer pads!! Hands down one of the best.
The rotors is a different story. I am waiting for Brembo to make them for the Sport runner (larger discs) but if you have the smaller ones then there is your answer.

I'm pretty sure that Brembo is doing the larger fronts now. I think someone posted the part number recently and I wrote it down and put it in my file for when I do the whole brake job. Search Brembo and you should come up with the thread.

 

[DanDLT]

has anyone found the fix for the pulsating brakes? i just changed new rotors and oem pads but still getting the pulsating brakes.. i can really feel it while coming slowly to a stop... i think its the front calipers.... any updates ????

 

[gizmopt2002]

What rotors did you buy? And do you tow?