Warped rotors 98 4Runner

[LukeZero]

I have been through 3 pair of front rotors on my 98 4Runner in the last year. The first set were cheapies put on by the guy we use for company truck repairs. The second set were put on by me and were better than just cheapies. I think they were $40 each from AutoZone. They warped within 3 months (1500 miles). The current pair are Bendix, made in the USA, ~$80 each and they are warping within 1200 miles. I tightened the lug nuts with a torque wrench to factory specs, so I don't suspect overtightening. What should I be doing differently? I don't seem to have a stuck caliper, because I don't have the rotors hot after driving normal trips.

Any suggestions would be nice, the rotors are under warranty, so getting another pair isn't the issue, and I'm getting good at switching them out, but that's not the point.

Thanks, Luke

 

[Ron Helmuth]

calipers and rotors from a Tundra?

Luke- I feel your pain- I went through similar issues with my 95 4Runner. (2nd gen)

The first thing the brake shop was able to fix was the balancing of the brakes-my fronts were doing too much of the work. I realize the fronts do the majority of the braking-but the rears have to pull their share as well.

I believe a number of 3rd gen Runner owners have upgraded to Tundra rotors or calipers or both.

Check out T4R forum for more specifics, there are several threads related to Tundra upgrades for the 4Runner. The general consensus I am reading into it is that the 3rd gen rotors are undersized

 

[WristPin]

make sure the rear shoes are adjusted snug.

the quaility of most AFTMKT rotors is really poor. and no matter what you do to fix it, is inevitable to get warpage

i install Centric rotors with very few comebacks. try that brand.

 

[LukeZero]

Luke- I feel your pain- I went through similar issues with my 95 4Runner. (2nd gen)

The first thing the brake shop was able to fix was the balancing of the brakes-my fronts were doing too much of the work. I realize the fronts do the majority of the braking-but the rears have to pull their share as well.

I believe a number of 3rd gen Runner owners have upgraded to Tundra rotors or calipers or both.

Check out T4R forum for more specifics, there are several threads related to Tundra upgrades for the 4Runner. The general consensus I am reading into it is that the 3rd gen rotors are undersized

There are other Toyota forums on the interweb? Who knew?

Actually, thanks for the suggestion. I guess I'm sort of reinventing the wheel here and other guys already have identified and corrected the problem. Once I get back from Rubithon, I'll begin to think about upgrading to the Tundra rotors and calipers.

And, WristPin, I will also check the rear brakes, that kind of makes sense that if the fronts are undersized, the rears need to do their share of the stopping in order to not overheat the fronts. Good suggestion,

Luke

 

[Duane]

LukeZero
What did you finally end up doing with your front rotors?
Just asking as I was in the mountains this weekend and braking on a steep grade before a corner and shudder city!
Thanks

 

[LukeZero]

I found the rears not doing anything at all, causing the fronts to do ALL of the work and overheating. After figuring this out and adjusting the rears to do more of the stopping duty (actually maybe a little too much), and installing new Bendix rotors, the pulsing is gone. But, its really too soon to tell if I solved the problem or if these rotors will also warp. I'll keep you posted.

 

[Duane]

don't the rears have an auto ratchet sort of adjustment each time you back up? Seems odd that you would have to adjust them.


Just found this in another thread regarding warping rotors......cheers..

And here's a tip: replace those with some Brembo rotors. If you replace with stock they will just warp again. I've had great luck with my Brembo rotors and new stock Toyota pads. 50k and a lot of trailer towing (including across the US) with no sign of warpage.

 

[flykrs1]

Make sure you consistently use the e-brake as this adjusts the rears. Also if the handle goes through more than 4-5 clicks there is a problem.

I have 91k on my original brakes and no warping and my favorite fishing spots are up in the Sierras and San Juans. Make sure you break in new rotors.

Now having said that, after much reading I will be doing the Tundra upgrade shortly.

There is a ginormous amount of information written on this topic.

 

[Duane]

thanks Flykrs1 as i started using the ebrake now....
Shall see how it goes... I also rotated my tires again as the one set must not be as round or well balanced as the others. Had them rebalanced...still more weights on them than the other set... how crazy is that as 2 tires need a fair bit more weights to balance them.... yet they still can shake at 70 mph...
An upgrade to the Tundra hey.... I was rather impressed with the size of the rear drums and the double piston front calipers on my 96 already. Bigger than an older half ton chevy pickup !

 

[mabrodis]

I also rotated my tires again as the one set must not be as round or well balanced as the others. Had them rebalanced...still more weights on them than the other set... how crazy is that as 2 tires need a fair bit more weights to balance them.... yet they still can shake at 70 mph...
An upgrade to the Tundra hey.... I was rather impressed with the size of the rear drums and the double piston front calipers on my 96 already. Bigger than an older half ton chevy pickup !

I need to address the brakes on my '96, they shake some...however, one thing I stumbled onto was on my '85 truck...it had horrible shaking when braking...I flushed the full brake system, made sure both calipers worked smooth (pushed them back with a clamp and then used brake pressure to slowly push them out), new pads, spring thingies, rotors, etc...get it all done and go driving and no change what-so-freaking-ever...I was pissed...I did the breaking the pads in several times (60-5 mph)..I just lived with it then a few months later I got new wheels and tires and every-damn-bit of the shaking went away. I already had the old semi-dry-rotted tires and factory steel rims balanced atleast twice and it never helped, so I figured it wasn't a balance issue...but apparently it was, because the new rims (used beatup alum ones) and new tires (31x10.50 MTRs) rocked...perfectly smooth. I was shocked, I never would have guessed it could be that.

So..the tires on my 4runner are also suspect, hopefully the rims are not though, but I have been waiting till I get the new tires before digging too deep into the brakes...just my $0.02...

Good Luck...if/when I actually pull the front brakes I'll likely replace them with the Tundra setup, I've read up on that some, but need to read more and get actual part numbers...

 

[Duane]

I agree with your experience with balanced rims/tire combo's.
I have sort of come to expect that a Goodyear can be out of round but Michelins usually balance up without much weight. Could be a rim though as well.

What made me wonder was why under certain braking it would shake badly and other times very minimal. My rotors do not appear to have excessive run-out as looking with a naked eye compared to the pad that didn't move.(poor mans dial gauge) No hot spots/discoloring on the rotors either.
As I think about how a tire/rim combo is balanced though, it really just corrects the balance but does nothing to tell you if the tire is out of round. Perhaps there ought to be a dial gauge with a roller on it to measure the run out when it spins on the balancing machine. If it's over a certain fraction of an inch ask for a different new tire. Sort of like hand picking the best ones. Then of course set a vehicles weight down on them and who knows what that does then? Not sure if a tire shop would do it but one should ask them to spin the bare rim and see how balanced and true it is when spun... at least then you know if the rim is good to start with and maybe just the tire is the culprit.

 

[mabrodis]

If it's over a certain fraction of an inch ask for a different new tire. Sort of like hand picking the best ones. Then of course set a vehicles weight down on them and who knows what that does then? Not sure if a tire shop would do it but one should ask them to spin the bare rim and see how balanced and true it is when spun... at least then you know if the rim is good to start with and maybe just the tire is the culprit.

Actually having a tire shop spin the bare rim is not a bad idea at all...and if it was out of balance you could just take a grinder to parts of it...damn good idea!

As for having a tire that's 'balanced' either in the air (traditional machine) or with weight on it (road-force machine) still doesn't mean the tire is actually round...I've thought about jacking the tire up an inch or so then running it and visually watching it, or putting some tool on it to see the runout of it...great idea...had some badly scalloped and out of round tires on our Echo, and rather than just replace them, I tried something...with the wife in the vehicle, jacked up one tire, then with her spinning it in 1st gear slowly lowered it until it was burning rubber, the car was firmly secured and all that and it actually did work some, it burned the wildly scalloped tread down and they were smoother, not perfect mind you, but it was only a test anyway, since ofcourse the tire shop would just toss them, so I wanted to try it...granted it took 2 weeks to get the burned tire smell out of the car...and rubber bits off the fender...and there is still a small hole in the street where the tire was eating away the pavement...doh! Next tire I did on concrete, that worked much better..