joebor1776

I still haven't identified the source of this popping / rattle noise, after having replaced all of these components:

Rear axle carrier bushings/bearings
Rear sway bar bushings
Rear swar bar end links
Rear struts and mounts
Taken out spare tire and everything in trunk
Removed front floor center brace (in case exhaust was hitting it)

The noise happens regardless of whether the brake is applied. It happens on acceleration sometimes, happens at idle sometimes (in park or in drive), and over bumps sometimes. Definitely sounds like it's coming from the driver's side rear. You can hear the noise in the YT video that I posted earlier in this thread.

I'm about at the point where I want to just pay the diagnostic fee at the Lexus dealer. But I thought I would check with you guys one more time first. I've done a ton of searching, and the only other possibility that came up was something like the driveshaft center bearing or the flexible couplings/guibo in the driveshaft. But that seems to be more of a clunk sound, not a pop-pop-pop or knock-knock-knock like I'm having.

Thanks, I appreciate any ideas...

joebor1776

Just to add to my list of things replaced while chasing this rattle: added FIGS supplemental bushings to the rear subframe, but that didn't fix the rattle. Not sure what the next possible culprit is...maybe the guibo/flex joint?

joebor1776

My rattle ended up being the left muffler banging against the Uhaul trailer hitch that the previous owner had bolted on. I should have listened to kamlung :-). It was tricky though--I had checked the exhaust for interferences, but I could not move the muffler far enough with my hands to reproduce the rattle, so it escaped me for months. Until yesterday when a really cool other GS owner helped me pinpoint the noise while the car was warmed up and running. I unbolted the hitch and now the noise is gone!

wolfy53

I know what you mean. I personally don't like pressing in and out bushings like these. Poly ones no prob.

I bought the whole bars bars worth the extra money for the convenience for me at least.

And if you are asking that question. Just get the whole bars. But that's just my opinion😉

jsull126

Saw this thread and wanted to ask about a clunck or knock (one time knock) sound I'm getting when I hit the brake pedal. I've got a 2007 Lexus 350 with 125K miles on it. Recently been hearing a cluncking sound coming from the left front wheel when the brake pedal is depressed lightly. A mechanic friend looked it over (quickly) the other day and said he thought it could be the struts. Before I take it to an experience lexus mechanic or dealer, could it be a loose brake pad or something loose in the brake assembly? He told me to keep driving it, that it wasn't a safety issue. It's gotten louder the last day or so and I think it's time to get it looked at. Anyone have a similar experience or thoughts as to what it could be?