OK, 2015 RX350... my wife has been complaining about a squealing noise when she starts up and drives for a bit. I assumed the brakes were getting sprayed by the sprinkler and creating a rust film on the disks.. her conclusion was to spray the steering wheel with WD40.. lol.. But today, I drove it, and it sounds like its underhood at the left front— like a squealing belt or a bearing going out—or what a power steering issue might be.. Then, after about 1 minute, it goes away,.., Also, if turned off, the noise will repeat. Steering affects the tone of the noise, as well. Where should I start?
Please remind me of the steering mechanism. Is it Electric? How does that work? No hydraulics? Anyway, feedback is appreciated. Please be patient if this is a duplicate post.
Also, I just spoke to my buddy, and he says his son's RX 350 always makes the same noise.??? wth?

Thanks as always,

 

Could be the water pump. A mechanic's stethoscope would come in handy in your case.

And yes, the vehicle has electric steering.

 

It has electric power steering and the serpentine belt is on the passenger side. If it possibly happens before you start moving you could listen with the hood up when someone else starts the engine.
It could be a number of different things. However these items are on the passenger side: Water pump, Idler pulley, belt tensioner, worn slipping belt, alternator, air conditioner compressor, or who knows, although I would not rule out a caliper issue, but it is very difficult to perform this type of diagnosis online.
You could post a recording using the "Go Advanced" feature as that would be very helpful.
If you are not capable of repairing them yourself, then it may be best to take it to a good local independent repair shop. I would not trust a dealer.

 

Thanks for the feedback.. ok, the input to the steering is electronic but the system is hydraulic... I can go from there...
Many thanks for your time!! Additional feedback is appreciated!

 

An update.. ok.. upon inspection, I saw a wear mark in the center of my new rotor... Thinking there might be something between the rotor and pad, I disassembled.. scuffed the rotor to remove any high points and did the same to the pad... Then swapped the pads ( inner to outer.. as a test)... Great news!! The squealing sound is no more when moving forward.. the bad news is the squealing it now happens in reverse... I think I have a pad issue.. feedback appreciated.. 👍

 

What brand brake pads?

 

Bosch Ceramic...the other wheels have no issues. Thx

 

I am not a fan of Bosh product in Lexus. [Just my opinion].

Salim

 

Too late now.. they worked great on my ML 350 and Armada.. thanks for the feedback..

 

Did you relube the hardware points, and the slider pins?

 

I lubed where noted in the directions. That doesn't mean there isn't room for improvement, lol. Thanks for the feedback. I'll pull the wheel on review once more.

 

Brake pad directions do not always include the caliper slide pins which are explained in this video.
​​​​​​