DIrEctQL

Okay so this is strange. There is a metal grinding/dragging noise coming from the rear passager side of the car. I have a '05 GX470 with air suspension. On the first look I don't appear to be dragging anything and everything looks good with the brakes. I also noticed the noise persists after stopping sometimes but when I shift to neutral it disappears. So here is my list of suspects:

- Eroded muffler (there was an exhaust leak)
- Air suspension because I don't know anything about it
- Differentials
- Transmission

Anything else I missed?

infinirx

I don't want to alarm you but I would get it checked right away and not even drive it. If it's a differential your just making it worse by driving it. How long since you changed the diff. fluids?

No dash lights or anything??

bauer26

Wait, so is the noise occurring *while* braking or when you are at a complete stop? If its at a complete stop I don't see it being differentials. If there was a prior problem with an exhaust leak I would personally start there.

If its happening while braking how close did you look at the brakes? I had a similar issue where while braking i'd hear a metal grinding noise, I couldn't figure it out until one day I had brake fluid leaking from my rear passenger caliper. It looked fine when I first looked at it (before the fluid leak) then when I saw the leak I took the pads out and noticed that one of the caliper pistons bit the dust thus eating through the pad then the back side of the rotor and eventually tearing itself up completely.

DIrEctQL

Still not sure what it is. It technically could be a broken diff because if your car is in drive, it puts a load on the diff and you're just holding the car stopped using the brakes. The noise happens with higher speed especially and while I can't replicate it anymore, I swear I heard it while stopped on a stop sign. I was driving yesterday and while the noise was occurring, I put the car in neutral. The noise did not stop. I really need to take off the wheel.

mann777

When I had done my skimming of brakes in the front, I missed one part, after many rides got this noise like grinding while braking, All I could hear was it was coming from below when I opened the driver side glass door to know the noise, Then later came to know the Right Side Front Wheel Brake Dust cover was loose, and bolts had not tightened. That solved the problem. Here is the image I am talking about.
Have u done the brakes recently, check this part, u never know.

DIrEctQL

Okay, thank you for all your help. I actually figured it out. It was a heat shield located above the catalytic converter. I can't believe how loud it was and it made all that noise.

infinirx

Glad you found the problem and it was not a really bad one.

bauer26

Glad you got it figured out and it wasn't something too expensive to fix.

atif7x7

Thank you for the info. Took the GX offroading and had this noise randomly. I was scared I damaged the suspension (even though it was fairly light offroad drive) but now I am relaxed ! ..Will get the heat shield tightened over the weekend !

DIrEctQL

Mine was completely loose.

real84

I have change the muffler and tail pipe for after market parts, and the parts are smaller that was on my lexus gx470 2005 it was 2.5in and now is 2in do you see any problem of lost of power or something...THanks!