It could be as simple as rust forming between the pads and rotors. My understanding is that disc brakes are "self-cleaning" ... normal brake use keeps the rotors bright and shiny as we can easily see between the wheel spokes. Parking a wet vehicle with water trapped between the pads and the rotors seems to be the culprit.

P.S. I only wash our vehicle at a car wash with high-pressure jets of water from all sides, but it sounds like you washed your GX by hand and had the same problem. Presumably, you washed it in your driveway, then drove it only 20 - 30 feet into the garage. There wasn't enough heat caused by friction to dry the brakes.

 

I hand wash my GX every weekend in my driveway spring through fall. I wash it every weekend at the high pressure car wash during the winter.

When washing in my driveway I wash the wheels and the car thoroughly, dry the vehicle, condition the tires, and back it 25 feet into the garage. Never had the issue you are describing.

During winter after visiting the car wash I drive the vehicle home immediately (about 1/10th of a mile) at 30 mph or less and back into the garage. Never had the issue you are describing.

If you truly suspect water is causing the issue then ride the brakes for a 10 seconds at a slow speed on your drive home or after you wash the vehicle. That will be enough to essentially dry off the brakes.

 

ive worked on cars for years, and never have seen a brake pad get stuck on the raw metal of the rotor. Can someone explain how a semi metallic or ceramic or composite pad gets stuck to metal? They are not made of the same material rendering adhesion quite difficult.
The rear brakes have a drum and pads inside that are the parking brakes. It is likely the springs and hardware rust making the pad difficult to release away from the drum, but the pad itself should never get stuck on the metal...

 

In my case it is a must to wash the car to rinse away winter road salt. Since I would never use an automatic car wash that physically touches my vehicle a high pressure, touchless wash is my only option in winter months. I've never seen an automatic, low pressure car wash .

 

If it is just rust on the springs and hardware it should be easy to fix ... spray those parts with a suitable rust inhibitor and lubricant, but don't get any on the braking parts. What is happening when I "drag the brake" on the way home from the car wash to prevent this from happening? I had assumed the heat would dry the brakes, but if it isn't the brakes than why is brake dragging effective at preventing this?
Regards,

SaniDel

 

I haven't had a chance to write again lately but we had another incident with the transmission. My wife started the GX and when putting it into reverse it made this loud noise again, with the brake depressed. The truck hadn't been wet for over a week prior and driven daily leading up to this. I'll call the dealer, get it in again and see what they find.

 

If the truck hasn't been wet lately and is driven daily, this does not sound like a problem caused by the brakes sticking. You are doing the right thing by taking it into the dealer although this may be a hard problem to replicate as it happens so infrequently.
Regards,

SaniDel


P.S. The problem I have with wet brakes sticking is so predictable that I've decided to sidestep the problem. On those days that I have the GX washed and bring it home immediately I force myself to overcome 50 years of habit and do NOT engage the emergency brake, relying instead on the transmission in Park.

 

I'm having some light noise from the driveline when starting out, say from a standing start to 25 mph. It seems to slowly go away as the speed gets higher, and also seems to disappear nearly completely after the car is warmed up. Its not a grinding noise, but maybe more of a "growl"....something that makes it feel like there's a fluid problem or something. This is a more recent development, and hasn't been there previously.

The only guesses that make sense to me are transmission, or possibly differentials/transfer case fluid issues. Anyone else have any experience with this? Truck has 70,000 miles and otherwise seems fine.

 

I experience it when engine is cold. Almost a humming sound until it gets warm. Seems to lack gear engagement until the engine warms up. I was curious about this myself and glad you brought it up in this forum. Any advice out there?

 

Happy I'm not the only one. Humming might be a better term than growling, but its always made a slightly unique noise at low speed in low gear.

It just seems to have become much more pronounced recently. Glad there's at least one other person who's perceiving this.

 

Purchased mine (2013, 90K miles) about six months ago. Took it in for service at Lexus dealership and mentioned the high rpms at startup. They said nothing was wrong and all fluids where fine.

On a side note, they found a oil leak around the timing chain cover, Estimated cost to fix over $2,200.00, I said no thanks, never seen any oil in carport where it's parked.

 

I've been dealing with a strange issue on my 2010 GX with 100k miles and wanted to document it on the forum in case others have a similar issue.

The issue started a couple months ago. It usually only happened on the highway between 40 and 60 MPH in 5th and 6th gear. While cruising in this range I started to feel a light shudder from the rear of the vehicle -- kind of feels like you're going over small rumble strips. It happened more frequently when trying to hold speed on a slight incline. When it happens you can take your foot off the gas and re-apply and the shudder will go away.

I knew this could be transmission related to I took it into a independent lexus service shop. They test drove it and felt the issue, then hooked it up for a diagnostic test. They determined it was a torque converter and would cost $2500 and possibly more if the transmission needed to be replaced. They also said they have NEVER seen a issue like this on a GX before and they advised I talk to Lexus Customer Care and my Lexus dealer to see if they can help.

I opened a case with Lexus Customer Care and went to the dealer. The dealer agreed that this was a very rare case. They performed a diagnostics test and said a software update would fix the issue. I said sure why not....but it didn't fix the issue. Two days later they said a Lexus engineer recommended pulling the drive shaft and inspecting some pins for $800 minimum...I said I wasn't ok with a $800+ diagnostic that sounded like it might not fix the issue. They did it on their own dime and it didn't reveal anything. Lexus came back and said it would need a new Torque Converter at a cost of $4500.

On top of that, Lexus Customer Care denied my request for assistance, basically saying that I am the 2nd owner of this vehicle (only had it for a year) and I don't have enough history with Lexus, even though the lexus itself has had every service and oil performed at a lexus dealer since new. The service record was immaculate which is why i purchased this particular GX in the first place. Not that I expected much from them, but they really should provide a nicer response to new customers.

So i told them I would need to consider my options and drove the car home. The car experienced the shuddering issue on the way home so I knew it wasn't fixed.

Here's where it gets interesting. The independent shop told me my battery needed to be replaced. When I took the GX home I already had a battery ready to go in so I replaced it. The car immediately died when I started it up after replacing the battery -- common issue when you have carbon buildup in the throttle body. I cleaned the throttle body and the engine cranked up with no issues!

I've driven the GX about 600 miles over the past two weeks since replacing the battery and cleaning the TB and I have not experienced any shuddering. In fact, it feels like it has a lot more power on the highway and accelerates without downshifting on inclines where it would shudder before.

Did I just save myself $4k? I guess time will tell but I am floored at how much better the car is driving.

Feel free to chime in if you've experienced anything like this before.

 

sTo avoid engine build-up, stop using low grade fuel consistently for long periods of time.

 

Why is this an issue when changing the battery?

Is this the same procedure for the GX 460?

 

The only logical explanation I can come up with that as you disconnected the battery for a while it reset the computer and it fixed your problem somehow. I don't see how the throttle body can cause vibration at high speeds.
BTW: I am surprised you had problems with dirty TB as these new electronically controlled TB systems are adjusting themselves if the plate and the wall gets some buildup.