I am used to my 87' truck. so the wifes 96 runner, 3.4 is kinda foreign to me. A year ago i had all the brakes pads replaced, front and back. However, a problem I had before and after still exists. In snow or icy conditions, it seems that one of the front brakes locks up well before all the others. There is a strange noise/hum that is heard while this is happening, along with a shuttering while trying to brake. I believe the front left brake is locking up before anything else as witnessed by the snow skid marks. This just sent my wife into a scary downhill slide.

Driving on non icy or snowy roads, everything seems fine.

I am perplexed

What do you all think? Calipers, M/C?

 

i would guess the noise/hum and shuddering signs of the ABS doing its job.

when i lock up on an icy patch, i pull a little to the right because my alignment is a little off.

another thing i would investigate is that the left front rotor may be warped, or maby different brake pads were put on the fronts.

 

Definitely the ABS, the noise is normal.

If it bothers you too much, you can delete your ABS system. It's not the best on the 3rd gen 4runners anyway, it can actually cause the brakes not to grab properly on ice and cause you to roll right through a stop sign at slow speeds. Sounds like your wife experienced how scary it can be.

It seems like my front driver side catches first on ice too, not sure why but maybe that's normal for our ABS too

 

I was in an small bumper accident years ago in my 4runner due to the ABS going all crazy and I slid into a guy at about 5mph after sliding on ice for about a block. It just buzzed and made all kinds of funky noises but did nothing to stop or slow me down even though I started braking LOOOONNNGGGG before any sign of trouble. The next day I pulled the ABS fuse and have been happily in control of my vehicle ever since. I do have a braking issue with one side grabbing before the other when hard braking but I noticed that before I nixed the ABS and I've done calipers and rotors twice since so I don't think that's the problem with mine. I'd like to completely eliminate the ABS system and get the lines for a '96/'97, I've heard sometimes the ABS system needs to be bled if you loose too much fluid. I was also told to check my proportioning valve(?) but haven't got to it just yet. Brakes were a priority this month until I was rear-ended the other night, now it's a frame swap and suspension to get back on the road.

Good luck with your repair, be sure to let us know what you found if you fix your problem as I would like to hear the diagnosis.

 

It sounds weird but I think you need to check rear axel seals. I had simalar front brake locking up. I thought it was a caliper and it ended up being a real axel seal leaking grease on the rear pads. In turn the rear pads started acting funny and affecting the front brakes. I was leaving fvront skid marks but it was the back brakes with the issue.

 

Excellent info, I'll look into both issues, thanks!

 

So far I pulled the ABS fuse, I thought I fixed the problem. New ice on the road proved that the front is definitely locking up before the rear. The noise and pulsating is gone since I pulled the ABS fuse. Have not had the chance to look at the rear seals due to ice and snow buildup.