Brakes

[samdajellybeenie14]

I just got my '99 4runner limited maybe a week or so ago (love it) and when I step on the brakes and get around 15-0 mph, there is a very slight lurching almost as if someone is stepping on and off the brakes, but only just. This isn't really THAT big of a deal, but I was curious as to what it might be... By the way, the previous owner had just gotten the brakes done maybe a month a before a bought it... Any help with this would be appreciated!!

 

[Sherwood4Runner]

I have a '98 Limited too and have the same issue. Very likely it is caused by warped rotors on the front axles. When the previous owner had the brakes done he might not have had the rotors replaced/milled. When the disc brake rotors heat up due to friction and then are cooled quickly (likely from water splash on it) 'hot spots', or ripples/bumps, are formed on the surface of the brake rotor. This causes the brake pad to grab more over the bumps and less over the flat surface which simulates that feeling of 'someone stepping on and off the brakes'. This isn't an impeding issue as far as safety but it sure is annoying. My local brake shop charges 80 dollars to plane/mill the surface of the front two rotors.

 

[samdajellybeenie14]

Thanks man. I figured thats what it might be. Now to determine if getting the rotors milled/planed is actually worth it, or if I should just wear them down until the become normal again. Is that actually possible?

Or should I just get new rotors??

 

[Mellow77]

It can be a number of things but the symptom you've described has been a result of warped rotors on several vehicles I've owned. Wearing them back down flat isn't really a feasible expectation. The warping is caused by heat and when a rotor is already warped the heat will always be uneven since it's greater in the places closest to the brake pad on contact if that makes sense. The "high" spots will receive the longest touch points in contact with the pads so they'll get the hottest.

I would suggest taking it back to the place that did the brakes to begin with. Even if they aren't under warranty they may be willing to cut you a break on the cost of surfacing/replacing the rotors as needed. Depending on the parts used some vehicles, like my Audi, aren't made to have the rotors surfaced. You technically can re-surface them but that leads to them constantly squeaking and being rather annoying. A good brake shop will help you find your best option because they won't want you back in the following week complaining about squeaky brakes and pulsating rotors.

 

[LodeRunner]

I agree with the others that this is most likely warped rotors... I've experienced this on a number of vehicles. I actually just replaced the rotors and pads on my '97 this past weekend. It's such an easy job it's almost a crime to pay someone to do it.

I got some Brembo rotors for about $70 a piece from Amazon, which is cheaper than the OEMs rotors and very high quality. If the shop that did them a month ago will fix it for you for free, though, then that's certainly the way to go!

Best of luck, and congrats on the new T4R.