More bizarre braking behavior.

[THEDK]

its a 2014 with almost 40k miles.

So lately, it's been smelling a lot like smoked brakes (Like how a car smells after a track day.) but I haven't been able to visually identify any issues. Doesn't seem like a stuck caliper. Some searching around, and more than a few people have had the issue and it might be "normal." That said, it's new-ish so I'm mentioning it it.


A while ago, I had an issue with the brake feel being pretty different from time to time. That went away too.

Today it did this weird thing twice while it was raining:

When braking with moderate/hard effort, the car would buck, like as if I was pumping the pedal like: BRAKE release BRAKE release BRAKE release.

You know how the brakes will pulse during antilock braking? Not entirely unlike that, but VERY slow motion. Also no ABS light.

Haven't been able to replicate it, and I have no idea what to look for. Is this a normal thing?

So far everything I've tried to go to the dealer for has resulted in "nah they all do that, no repair for you" so I'm asking here.

 

[BigredTEX]

You don't identify which model you own, but your previous post about brake issues from April says "14TE".

Is the vehicle stock or has it been lifted? It sounds like it possibly could be the stability control kicking in randomly, but that would be accompanied with dash lights flashing.

Any other info you can provide?

 

[bofa]

Most shops that do brake jobs will do a free brake inspection. If you arent sure what to look for, id take advantage of that.

Personally id check the rotors and pads for any irregularities. You could have accidentally sprayed them with something or picked it up from driving.

 

[THEDK]

yep, trail edition, 100% stock. original tires/brakes/etc.

The rotors and pads look OK visually. It does vibrate a little like it has rotor deposits on braking, but apparently that's also "normal"

Fortunately no one was in front of me for either incident, because it took a LONG distance to stop.

I'd already been driving about 20 miles when it did it.

 

[(none)]

The ABS light does not illuminate when the system is functioning. You should be able to hear it working though.

 

[THEDK]

The ABS light does not illuminate when the system is functioning. You should be able to hear it working though.

ah okay, yeah it didnt make any noise either I'd expect with ABS. My last car lit up an ABS light when the system was activated so I kinda assumed the 4r would too. it was literally like:


.5 seconds: braking
.5 seconds: no braking

.5 seconds: braking
.5 seconds: no braking

.5 seconds: braking
.5 seconds: no braking


It took a LONG distance (like 3x normal) to stop from 50mph. That could have gone pretty bad.

 

[tm965]

ah okay, yeah it didnt make any noise either I'd expect with ABS. My last car lit up an ABS light when the system was activated so I kinda assumed the 4r would too. it was literally like:


.5 seconds: braking
.5 seconds: no braking

.5 seconds: braking
.5 seconds: no braking

.5 seconds: braking
.5 seconds: no braking


It took a LONG distance (like 3x normal) to stop from 50mph. That could have gone pretty bad.

go to the dealer

 

[THEDK]

go to the dealer

dealer is 110% worthless. that's why my t4r steering still shakes like it's falling apart when i accelerate over 2k rpm..

 

[SR5Bart]

dealer is 110% worthless. that's why my t4r steering still shakes like it's falling apart when i accelerate over 2k rpm..

Looks like you got a crappy dealership. Im 100% sure however that it is not the only one in your area. Instead of wasting time asking people what it might be get someone to look at it. Nobody will ever diagnose an issue through the interwebz

 

[THEDK]

Looks like you got a crappy dealership. Im 100% sure however that it is not the only one in your area. Instead of wasting time asking people what it might be get someone to look at it. Nobody will ever diagnose an issue through the interwebz

There's one I haven't tried yet, but it's fairly far away. might be worth a shot.

 

[Heavy_GD]

I vote warped rotor...

 

[THEDK]

I vote warped rotor...

It def. has deposits on the rotor. I'll go through the bed in procedure again at lunch on some empty roads

 

[SR5Bart]

There's one I haven't tried yet, but it's fairly far away. might be worth a shot.

There are for sure dealers out there that don't care and are garbage but sometimes you can find that diamond in the rough

 

[THEDK]

Just drove around a while and did a lot of panic stops. No problems at all.

This car. :noidea:

 

[FrontRange4Runner]

Sounds sketchy AF. I would do what someone above suggested and take it to an independent shop. If they can find and document anything, you could then go back to the dealer with some real ammo. Also, you might want to get Toyota USA on the horn and tell them whats going on. They may be able to put some extra pressure on the dealership for you.

 

[pitstain]

Possibly an issue with the brake booster or the electronic brakeforce distro systems?

It really needs a full riding diagnostic by a dealer with the techstream laptop riding shotgun.

 

[catrains]

Just drove around a while and did a lot of panic stops. No problems at all.

This car. :noidea:

I have had this on a few vehicles one vehicle 2 yrs old had this with 30K miles on it, .. what I believe happened was I lived in VA and the streets would flood out about 1-2ft of water . well what happened was I had those vibs in the steering wheel and the brakes did stop poorly.

I found that the calipers pistons rusted as the water got into the dust boot. I popped out the pistons removed the rust and installed new seals , used a silicone brake grease on the dust seal and had no problems for 8 yrs and 120 K miles when I sold it. rotors did not get damaged so I lucked out,,,.

on older vehicles like 10 plus years in the rust belt this will happen .. so to reduce this from happening I apply the silicone brake grease on these dust seals even when 10 miles on the vehicle new.. have had better luck with this happening ..