Random rattle noise on 96 LX450

[maineidyl]

Having a strange rattling noise under my LX450. Only happens when moving. Does not seem to be be related to bumps in the road or other issues. Can rev motor and still not hear any rattle. Is there a common problem or issue that plagues these. Have owned for 15 years never heard it before. Random rattle, never consistent.
TIA
Tom

 

[zapatius]

Having a strange rattling noise under my LX450. Only happens when moving. Does not seem to be be related to bumps in the road or other issues. Can rev motor and still not hear any rattle. Is there a common problem or issue that plagues these. Have owned for 15 years never heard it before. Random rattle, never consistent.
TIA
Tom

Most likely one of the heat shields. Give them all a tug.

 

[LandLocked93]

Yeah, heat shields...to include the clamps on the exhaust pipe covers just ahead of the cats. The clamps can rust through, yet remain attached. And the ends can rattle at certain RPMs against the exhaust cover itself. It's not the whole of your program, just thought worth a mention to look at.
I ended up using 1/2" stainless steel bands (ss zipties) to replace the clamps on those covers.

 

[maineidyl]

Did a quick check and could not budge the shields. Going to check further this weekend with motor completely cool. I just drove over 1/2 mile over a root infested road and no noise. Then in a flat section the hollow steel rattle sound came around for 2 seconds and stopped. I think it was when I applied the throttle after coasting for a minute. Its the strangest thing. I was worried at first that it was my u-joints or drive shaft issues.

 

[Halfpint]

I had a random rattle on my 97, sounded like it was coming from PS front engine/wheel/suspension- went from front to back underneath it with a rubber mallet popping every bushing, bar, shaft, component.... got all the way to the rear PS side and it was the rear spring had unseated its rubber spacer (which was basically deteriorated) after airing a speed bump at the plaza and would occasionally get in contact with the upper retainer and rattle....blew my mind how that sound traveled all the way to the front corner.

Get to tapping?

 

[Enders]

Squeaks and rattles that I’ve found
1) random s*** the wife leaves in cup holders
2) exhaust hanger bushing. This one is aft of the cats. Follow the hanger up with your finger to see what’s left of the rubber bushing. Mine was toast. Spent a few bucks with Joey at wits end
3) LCP’s front sway bar disconnect cotter pin. If the catch is allowed to sit on top of the sway bar, it can rattle. For me, it rattled on even ground, at idle. Heat shrink on the cotter pin catch fixed it. It was only on the passenger side.
4) bushings started to fail on my icon shocks. Not usually a big deal, except the front passenger but doesn’t want to do anything but spin. Just ordered some Dobi MRA’s to replace.

 

[TYM4FUN]

Also, loose intake in passenger fender.

 

[AJP]

I have had a front PS sway bar bushing disintegrate and cause a random rattle on my '97 LX450

 

[Gunsmoke76]

Did a quick check and could not budge the shields. Going to check further this weekend with motor completely cool. I just drove over 1/2 mile over a root infested road and no noise. Then in a flat section the hollow steel rattle sound came around for 2 seconds and stopped. I think it was when I applied the throttle after coasting for a minute. Its the strangest thing. I was worried at first that it was my u-joints or drive shaft issues.

I may be experiencing something similar. I can make it happen in overdrive. It happens in the space between driving and coasting. Not pulling, but not completely off the throttle. The faster the speed, the more pronounced the sound. DS? UJ?

 

[Rusty Marlin]

Shaky mirror bracket; had this one last road trip. Tightened the screw in the bottom of the mirror and my random buzz from the PS door went away

Broken trim around the sun roof... drove me bat $hit. Finally just broke it all out and no more rattle from above.

Pens and pencils in the door pockets.
Loose change in the square bucket under the cig lighter.

This one is self induced, my attic shelf. I have it on rubber insulators made from gas line, but it still rattles at high torque load, low rpm.

 

[LandLocked93]

I may be experiencing something similar. I can make it happen in overdrive. It happens in the space between driving and coasting. Not pulling, but not completely off the throttle. The faster the speed, the more pronounced the sound. DS? UJ?

U/js or ds yoke.
Give'em a grease job and re-eval.
If no change after a test drive, and you can't budge the yoke by yanking on it, prob need u/js.

 

[b16]

Squeaks and rattles that I’ve found

3) LCP’s front sway bar disconnect cotter pin. If the catch is allowed to sit on top of the sway bar, it can rattle. For me, it rattled on even ground, at idle. Heat shrink on the cotter pin catch fixed it. It was only on the passenger side.

I did my own version of the LCP sway bar disconnect. After getting so fed up with a rattle I couldn't find for YEARS I came across your post. Saw the handle thing on the pin was resting on the sway bar. Moved it up out of the way and the rattle was gone! How could that little thing make such a god awful rattling sound!? THANK YOU SO MUCH!

Now to heat shrink it like you did.

 

[Jbird Lexus]

Saw this a little post a just now after having very similar issues.. at highway Speed and at slower speed between 30 and 40 mph. Only When I let off the gas, in between accel/decel[ coasting.] I would get a huge grinding noise. I thought it was the rear diff or transfer case gears grinding... was very loud and horrible sounding... I removed the rear drive line and drove on the front with the center diff locked Thinking that would solve the problem. But I still had it now coming more from the front. After racking my brain for hours I finally disconnected my front hubs, Yes I have AVM hubs, And ran the truck without the hub's locked, stationary, so that the transfer case and front diff was turning... At first, there was no noise until I gave it a little gas and then let off. And then the horrible Grinding/ clanking noise appeared steady. It was the drive shafts. My drive shafts were installed By someone else, out of phase, where they you joints were not lined up... Also U joints appear to be loose though not bad and probably needed greece... I'm off to get the drive shafts balanced and greased up To solve the problem.. Here is a video: