Phil676

05 GX 470...no KDDS...100k miles

When I've been driving a few miles, I feel a pulsating when breaking. Feels like it's coming from the front (front left if I had to guess). I put in new rotors and brakes in the front, turned the back rotors and problem still persists, no improvement.

I'm now considering the hub-bearing. However, when I do the standard-check (lift wheel and apply stress from top/bottom) there's no indication of a bad hub bearing.

The problem worsens as I drive faster. When on the highway, if I start to turn the wheel right 'then' brake...the steering wheel pulsates bad. When I turn the wheel left 'then' brake, it's not as bad...but still noticable. When I start pressing the brake pedel 'then' start to turn the wheel right it's still there but not as bad compared to applying the brake after turning.

There's no pulsation in the break pedal, only the steering wheel and body/chassis.

Can anyone let me know if this is a true hub-bearing issue before I spend the cash/time?

IanB2

I'd look at 2 things, cheap and easy to do:
-make sure the brakes have been properly bedded
http://www.zeckhausen.com/bedding_in_brakes.htm
-rotate the tires, see if the issue persists. You could have a seperation in one of the front tires causing the vibration.

If these don't work, all you're out is time, and you can rule some obvious things out.

Phil676

Thanks Ian...didn't consider rotating tires, which don't have a lot of life left. I'll give it a try and report back.

Crispy3M

Sure sounds like a stuck caliper.

When you brake, does the vehicle pull to one side? Generally, if the truck pulls to one side, that is the side that's doing all the work. Meaning that the other side is stuck or seized.

After a quick drive around town, is one wheel much hotter than the other? If it's a stuck caliper, it will be very obvious.

I know you said new brakes, but that doesn't always mean that the garage doing the work has a clue... and the GX is famous for stuck calipers.

Cheers,

C3M

Phil676

Thanks crispy. It doesn't pull, only pulsate. I checked rotor temp and was close to 140 w about a 20 degree varience. I installed the breaks and used Wagner pads and o Reilly 's house rotors...resurfaced the back rotors. Pads didn't show uneven wear.
After I rotated tires (thanks Ian) and felt the pulsating differently, and I bought new (nice) tires...wouldn't have made it through all winter anyway. Unfortunately, the familiar pulsation returned...it felt better, but the way I remembered it months ago. It probably was the cause for the bad tire. It feels like an unbalanced tire when breaking at any speed....worsens with speed...so bad at 50 and above it starts to shake the body too. I keep thinking the new rotors must be bad, but No pulsation in brake pedal at any speed...only front end and steering wheel (slight-fast jerks to the right)..Car drives straight and tight otherwise.

mann777

Have you installed the Anti Squeal Shims ( recently there is anew replacement part come which I believe is better than the previous one ) And make sure some graphite grease is applied. And also make the sure Anti Rattle pins are installed properly ( when installing the pin hole clip with the handle is facing to the vehicle centre)

Phil676

Thanks Mann & Crispy...I just picked up the shims from lexus. They told me to put the graphite between the shim and the pad. What he couldn't tell me is if I should leave the original shim on the pad or take it off before putting the new shim on. Any suggestions?

Would you use a typical anti-squeal silicone between the caliper and shim (thinking this wouldn't hurt) considering these 'new' shims?

Phil

gxman1

I will let pro answer. I will tell you my experience few weeks back.

Driving on highway 50+ speed applied brake, and the steering wheel would shake - left to right. The brake felt pulsating. However, at lower speed minor conditions described above.
I looked at the pad, lots of it left, the rotors no groves and looked ok.

I called the lexus tech who has his own indy shop, he said he will turn the rotor on the vehicle without taking the rotor off. It will cost $90 to turn the rotors.

I decided to buy the parts at toyota dealership, new 2 rotors, new pads and shim kit. Shim kits was expensive around $60.

Shims are total of 8 (4 slotted and 4 solid). basically the brake job was easy, and I applied the grease which came with the shim kit. I applied on the back metal of the pad and between the slotted and solid part. The part touching the caliper NO grease.

By the way, when I took off the pads I noticed it was aftermarket and the shims were also aftermarket, the shim was small and part of the shim was not completely touching the caliper piston, uneven. It was a monroe brand shim.

After the change i did the break in routine, and my truck is like brand new when breaking, I drove 1800 miles recently around mountain and breaks worked perfectly and no pulsating.

You would discard old shims, since you are using new shims. Another thing I want to mention. There are post here and other places, telling people to buy the pads that comes with the shims and it is made in the USA all for around $60. I went to the dealer and compared the 2 and the Japanese made are much better and do not come with the Shims. I paid double but got the stock.

mann777

Full agree with GX on the discard of the old shims !!

Phil676

Well...didn't work. Intalled new shims (all 8) with grease...vented shim against pad and solid shim against vented shim. It felt great for the first few miles, then it pulsated...no change. I swapped brake pads and rotors from one side to the other...no change. I mic'd the pads and one is .040" thinner than the others (newer pads). Time to throw another part at it...caliper (Crispy called it).

I'll let you all know. Thanks everyone!!

Crispy3M

Any luck with the pulsating?

Phil676

Nothing. New caliper, second new rotor. Went over back brakes...all seems good. Friend suggested brake lines (still trying to wrap my head around that) and the ones I have look fine. Took hub bearing off and seems normal. Spins free and no noise. There is some/little white grease on the back of the bearing where it meets the half shaft...so that's where I'm at. Contemplating changing it out and seeing. The hub seem awfully difficult to get off the bearing. The whole assembly is 3-350...vs 1-150 for just the bearing.

jmgraham78

I am a NOOB to the GX forum, in fact this is my first post. Just picked up an 08GX and so far love it. Couple little CEL issues followed by the VSC lights, so in the process of tinkering to get that fixed.

As it pertains to your pulsating.... it is possible that it could be a wheel speed sensor.

My daily driver is an Audi Allroad, and the same symptoms and troubleshooting that the OP did, I had done as well. Changed the wheel speed sensor and the problem never returned.

J

fishhuntnc

Thought I would share a related experience with my '05 - 67k miles. It developed a brake judder back in June - steering wheel shaking, especially with higher speed braking. Original front rotors were replaced in June, along with new pads. Four months later, the symptoms returned. I had the rotors turned and the tech said the right front was very warped. Shortly after, noticed the symptom was still there. I felt the rotors today after coming home from work. The right front was sizzling hot - the left front was much less hot. Suspecting a stuck caliper, I jacked up the front. The front left wheel spins freely, the right front wheel barely spins at all - stuck caliper. Took off the wheel and brake pads, checked the caliper pistons and only one of the 4 pistons was working. Picked up a reman caliper this evening, installed, and viola - all problems are gone ! No more shaking and no more high heat coming from the right rotor.