Rear brakes engage first?

Hey, guys.

I'm Mister Lazy Azz on my 2019 TRDOR that I bought new in 2018. On all my previous vehicles, I did nearly all the service. Anyway, yesterday when I got my oil changed, etc., the service guy said my rear brakes were at 4mm and fronts around 6mm (I think). My experience on all my previous vehicles has been that the fronts wear down first. The guy explained to me that on the 4R, the rears are set to engage first to help reduce nose dive a little. Anyone else familiar with this? It makes sense to me, just wasn't aware of it.

 

I call bs. That can cause dangerous handling if you’re not going in a straight line.

FWIW none of my pads have lasted more than 60k miles.

 

I'm at 70k with the original pads, so it looks like I'm going to hit 100 or so. Mimics my previous experiences with brakes on Toyotas, unless I went aftermarket. I'm a light braker.

As for the rears braking first, it may be only a tiny bit earlier. I really don't know. I certainly don't notice anything different, nor anything unnerving. I don't see a reason for a service writer to make this up.

 

Well that’s mostly mountain driving.

 

I'm now doing searches. Apparently, things have changed since I last did brakes. "Another factor that has accelerated brake wear (especially rear brake wear) in certain late model vehicles is the change to electronic brake proportioning. The proportioning valve that normally reduces hydraulic pressure to the rear brakes has been eliminated so the rear brakes will handle a higher percentage of the brake load and be more aggressive. The antilock brake system performs the job of brake proportioning by keeping an eye on how the rear brakes are behaving. If the rear brakes start to lock up when braking hard, the ABS system kicks in and cycles pressure to the rear wheels to prevent them from skidding." So the short answer is probably that rear brakes now wear more quickly. Or so it seems.

 

No consumer road going vehicle sold anywhere in the world has a rear brake bias. Additionally it would make zero sense to have larger front brakes and rotors and then bias them to the smaller rear brakes.

 

Just stating what I was told and what I’ve read.

 

my wife always says that if I don't know the answer to something I just make something up. sounds like I have a twin. that said...I'm gonna ask around and see, always possible to learn something new.

 

I'm not mad at you

But, that service tech is an idiot haha

 

I just changed my front pads. Rears looked like they have plenty of life in them. Probably ready to be swapped out when the fronts wear out. changed out at 50k and still had a decent amount of life in them. I also am skeptical about what that service guy said.

 

Could be. But since I found the same thing on different websites, it must be a real thing. I’ll know more when I actually replace the pads.

 

Care to link where you found the 4Runner or any vehicle having a rear brake balance? I'm curious.

 

I would like to figure out how to get the rear brakes to do more of the work.

 

He's your crappleganger!

 

If your calipers aren’t seized just change the pads & if needed rotors also, 2mm isn’t that much difference i think if it was more like 10mm or more difference then i would be looking for sticking pads, seized slide parts & or frozen calipers.
Front pads wear down first if you are hard on the brakes lots of stop and go braking.

 

Trying to find the one I quoted last night, no success yet. Here's a couple that I just found about EBD:
https://www.brakeandfrontend.com/electronic-proportioning-valve-doing-more-with-less-hardware/
https://www.aa1car.com/library/brake_balance.htm

 

Just want to point out the front brakes are significantly larger than the rear, probably for a reason.

 

I experienced the same thing the OP mentions with my previous 2010 FJ Cruiser. Having the brake pad wear checked every 10K miles during oil changes and tire rotations showed the rear pads would wear down faster than the fronts. But not by much. Maybe 1mm or so. But I did think it was curious, but not an issue.

 

Hey OP,
My experience is the same as yours. I posted about it on T4R.org back in 2018. Here's a link to my post and the responses I got, along with a pic of my brake pads. Looks like I had a lot of people with the same experience as well. Good luck.

 

Thanks for the link. Yeah, my experience has been that my rear brakes outlast my fronts 2 to 1 or better. This is the first vehicle I’ve had where that’s different. Makes sense to me. The service writer’s comment that the rear brakes engage first may or may not be correct, but I get the concept. Not gonna beat anyone up over this. It’s simply news to me.