My 2002 4runner has been making some strange sounds related to braking lately. I just got back from a 1000-mile trip and here's what I have been experiencing:

1. When I brake and come to a complete stop, sometimes I will hear something working (sounds like an electic motor) and then it finally stops with a ping coming from the right front rotor (at least that's where it sounds like it is coming from when seated in the driver's seat). Tough to explain, but when it happens, I hear
'vvvvvvvvvvvvvvvvvvvvvr ping"...then all is fine. I feel like there is a motor running the right front caliper and it eventually releases (it is not an abs racheting sound). But that doesn't seem to make sense as far as I can tell - the truck just has brakes, fluid and a master cylinder, right? Or is this sound part of the TCS or some other system? I understand, according to the manual, that we should expect to hear funny noises at start up, but this noise is random, not at start up, and too strange to be normal.

also,

2. The brakes are very touchy, aspecially in the morning. Hit the brakes lightly and the whole truck wants to stop. This may not really be a problem, could be rust developing on the rotors overnight - dunno.

I will pull the right front wheel and make sure everything is looking ok asap. Is there an abs sensor or something that could have a rock in it? Could my caliper be rust bound? <img src="/forums/images/graemlins/rolleyes.gif" alt="" /> Thanks for any input! <img src="/forums/images/graemlins/kewl.gif" alt="" />

The sound is normal... It's your ABS. It's a mildly annoying feature on the wifey's rig too. There's nothing actually 'wrong', just a noisy operation. <img src="/forums/images/graemlins/cheers.gif" alt="" />

I don't know if that is good news or not! So, the noise will happen regardless of whether there is wheel slippage or not (i.e., it will happen on dry pavement)? Can anyone else confirm that they experience the same?

Thanks! <img src="/forums/images/graemlins/cheers.gif" alt="" />

neither my 3rd gen or 4th gen make this noise however I have heard noisey ABS pumps before. It still warrants a look though. Take the tire off and look for anything unusual. Take your vehicle onto a gravel road and do a few hard stops. Check the tire patern in the gravel to make sure all tires or applying a somewhat even pressure. Although it won't skid, it should still leave some marks. If something is wrong you might get a hard pull or a skidding tire.

Might also help to jack up the front end and slowly rotate the tire listening for noises.

If its coming from the right front corner then it sounds like it is the ABS actuator motor and it should not be activating like that unless you actually engage the ABS system. And to do that you have to be going I think above 15MPH or so and then if you try to stop quickly and you have limited traction or loose gravel or the likes it can trigger the ABS to go active. There could be other things causing this to occur but by all means get it looked at as it should not be occuring under normal braking conditions.

Maybe some others will chime in here with additional info. Hope this helps.

Ricochet

I drove around last night and became convinced that something is wrong. It is happening much more frequently now and on dry pavement. I will be pulling some wheels this weekend. <img src="/forums/images/graemlins/barf.gif" alt="" /> Jeeze, I got a toyota so that I wouldn't have to pull out the wrenches.

Not true... The ABS system comes up at startup & will activate at anytime, not just above 15mph. It'll kick on to keep the system pressurized whenever it falls beneath a certain threshold. Some rigs have more bleed-back than others, so it can happen more frequently & some are simply noisier than others.

Not that I inherently believe what the stealership says, but I too was paranoid about the sound... 3 of them have said the exact same thing re: the wifey's rig after inspecting the sound - Normal & within spec. Her's does it after every 5th pedal application; Has for 4 years (67k mi) without issue.

John, this is, in fact, normal. It's the ABS recharging, and the noise is prevalent on the 2001 and 2002's. You're wasting your time if you go to dig around in there. But, suit yourself.

yep, i'd agree with the others...normal...kinda like a hisss then a pop? my first 02 sr5 did it, and my 02 sport now, does it. usually when first started in the mornings, and also when coming to stops.....I've heard even lexus' do it to, although not as loud. i'd say it normal.

Ok, you have all convinced me that things are ok. My saab, which was kind of a piece of chit, never made a sound unless the abs activated in a skid. My toyota sounds like it is broken. I need to pay less attention to my vehicles. AND I will starting today! Thanks all - I am convinced! <img src="/forums/images/graemlins/kewl.gif" alt="" />

Anyone pull the abs fuse? I looked for it last night, but only in the cabin, and it wasn't in there as far as I could tell. I guess you would have the abs light on on the dash - that would be lame. My conclusion is that the traction control and abs are way overthought on this vehicle. <img src="/forums/images/graemlins/rolleyes.gif" alt="" />