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Discussion Starter #1
When applying the brake, the van kinda shakes. That would surely be in the front wheels. Would that be the rotors or the pads causing this? I read a lot on such culprit - possible warped rotor.

Thanks and stay safe!
 

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Shaking is the uneven application of braking force. Most often it's a combination of pad and disk - uneven thickness on the rotor from pad material transfer or coverage in one spot from sitting too long.

I think COVID driving habits are fueling a lot of brake issues.
 

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Discussion Starter #3 (Edited)
Shaking is the uneven application of braking force. Most often it's a combination of pad and disk - uneven thickness on the rotor from pad material transfer or coverage in one spot from sitting too long.

I think COVID driving habits are fueling a lot of brake issues.
Guess the safest thing would be to replace both the front rotors and the brake pads.
There are ceramic and semi-ceramic brake pads

Now, what is "COVID driving habits"? :D This is a new one for me.
 

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What does "the van kinda shakes" really mean, though? If you hit the brakes hard-ish, ABS will pulse the brakes to keep them from locking up. Vibrations could be from a warped wheel, bad wheel bearings, some worn suspension component, warped rotors, unevenly worn pads or pads which were never properly mated to the discs in the first place. Back in the day, rotors could be turned down on a brake lathe 2-3 times before needing to be replaced, but now, if you replace the pads, you typically just replace the rotors. Thanks to mediocre manufacturing/QC, you have to turn brand new rotors down before ever installing them in the first place too. At a minimum, I would lift your front end and pull the wheels to check for brake wear, plus give the whole front end a once-over inspection.
 

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What I was referring to was the drastic change in vehicle usage brought on by the pandemic. I switched to working from home for long stretches, meaning that my Subaru hardly left the garage. Same with wife and daughters. Two cars in the garage, two cars outside. Suddenly we began having those kind of brake issues.

When you move the vehicles and look carefully at the rotor, you can see the imprint of where the brake pad sat for long periods.

If the car was parked dry, the spot where the pads sat is typically clean, while the rest of the rotor has surface rust.

If the car was parked wet, the spot where the pads sat can sometimes develop substantial amounts of rust due to the trapped moisture, whereas the rest of the rotor has only light surface rust.

Either condition will produce a thickness variation in the rotor to a varying degree, and it can take a substantial amount of driving before it evens out. In the extreme (early in the pandemic when there was still a lot of salt on the roads), some said that their rotors were effectively ruined and needed to be turned (lathed) to even them out.
 
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FWIW, we've had some shaking while certain braking on our 06 AWD I believe the whole 12 years we have owned it. We live on a mountain, and coming down the big hill (8900' to 6700' in 5-8 miles) this happens. It seems to only be then (thus once the rotors are hot), and if you apply the brakes harder you still have braking power and it goes away (ie not really a safety thing). I also had this on a '98 automatic 4runner, whereas my trusty 5 spd '92 4runner doesn't get this, because I downshift. This all really points to warped rotors or ones that warp when hot, and that makes sense since it's hard to keep them from warping when they get hot and then get some slush splashed up on them.

OTOH, it didn't go away when replacing the front rotors. I replaced them at 155k or so, and they were still within spec. I've also replaced the pads a few times (the front have averaged maybe 35k, just like the tires). I also replaced the passenger wheel bearing. But, given the problem existed even back at 60k or so, and it only seems to happen when the rotors would be hot, it really points to that. I went with decent quality rotors that have a warranty, but they were from online and I didn't have them turned just before install. If your issue points to this, I'd suggest going big and paying extra for high end vented/drilled ones, and having them turned or at least double checked.

Test out your brakes. See if it's only when the rotors would be hot, and if when braking harder you still have brakes and it goes away.
 

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Best solution i did... Get autozone gold duralast rotors and pads... Lifetime warranty.. So later on when it does start shaking take pads, rotors for warranty..
I was surprised by the quality of these pads.. They stopped pretty fast and no shaking, pulsating so far.. 20k miles and counting..

Most other pads, rotors i tried .. They all started shaking, pulsating or whatever after 15k miles or later.. Thats factory toyota, 2-3 pads., akebono pads, powerstop rotor, pads combo.. Slotted, z23 pads i think..

Make sure grease the pins really good, I used synthetic grease.


Sent from my SM-N960U using Tapatalk
 

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That lifetime warranty at auto zone apparently also includes wear, so you don't even have to have a problem with them to get a free replacement. It sounds crazy, and I was sure the sales kid at the non-local store where I bought the first set was mistaken, though it did get me to go up a level. At least 2 of my 3 sets of pads (rears on the 4runner are drums) are now through them. We might be upgrading both vehicles relatively soon, but with this crazy setup auto zone has on this, I'll be buying the top of the line house brand ones as long as they continue to perform well, which they have so far.

(I did have a crazy thing, I think on the '92 4runner, where several brake pads I bought were wrong, misaligned a little. This included a set I bought online, and then multiple sets from auto zone. Even going to the mid level there were problems, but I got so I could change them in 15 minutes, and I ended up just bringing my tools and changing them out in their parking lot. They helped make it right, and I think there must be a master spec somewhere that got messed up, or a manufacturer that got screwed up. Misplaced pads on the backer can result in them not striking the disc right, giving less braking power. On one set that was hitting the raised rim of the disc, along with overhanging, it was significant and scary.)
 
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