Rx300 Noise

[L3XUS MAN]

Hey I'm not sure if this is normal but now it's starting to bother me. Occasionally while driving my 2003 rx300 I will hear a noise coming from the rear (well it seems it) of the car. It's not so much a whining noise, or a clicking, but more like water moving through tubes!! That's what it sounds like in my mind. I can't say that its just during accelerating, but it happens for no reason at all. Say I was driving 30mph on a residential road... This nosie would start, I would press the gas, no change. I would keep going, and it would just stop automatically. could it be brakes? I'm not sure it puzzles me. I wish I could say more but i can't. It's a very unusual sound. It really sounds like water moving through tubes or something. Does anyone else have this sound sometimes? Please I need to figure out what this is. My rx300 is a 4WD model. Please tell me it's not the transmission.

Thank you anyone who owns/has heard of this in an rx300.

[lexus ls430]

I have the same exact problem in my 03 rx300 2wd model. Is it more like a vibration from the rear. I have the same problem when i hit the brake.

[inautix]

I have same problem but it coming from front under glove compartment. It happens while car is even in park gear.