Hi. I'm planning to change out the stabilizer bar bushing on my 06 400h w/ 194k miles.
Have a "rattle" on passenger rear on shaky roads(not smooth, not potholes). Car drive fine, straight

Questions:
Can I just slide in under the rear of the car without lifting it up (enough space)?
Do I need to get the tires off the ground?

It's been awhile since I've worked on any suspension so excuse the basic questions. Last time was changing out the struts about 10 years ago.
I plan to follow this video on YouTube for 2010-15 RX... figure it would be simillar
Tools I'll use are basic socket set, electric impact wrench, torque wrench..
OEM bushing set (2) is about $25 shipped
Aftermarket bushing set is about $10. I'll probably get the aftermarket since it's closer, and this part isn't really a life-threatening part.

Additionally, I'm getting a minor metallic clunk on the rear passenger brake area. It sounds similar to the parking brake releasing sound.
Only happens when I'm stopped, release the brake, and pressing on the gas. The second I press the gas (lightly or heavily) it makes a faint noise described above.
I don't think this is the stabilizer bar bushing, but who knows. Already checked the temp of brakes after a drive (all same). No leaks on shocks. Pressing down on that side of car doesn't make noise.
Any experiences with that?

TLDR: Can a village idiot change out the stabilizer bar bushing?

 

Sounds to me like it may well be your sway bar links rather than the sway bar bushings, at least that was my case. At those miles best to replace both the bushings and the links but if you wish to test the links just try twisting the link itself, if it move freely at all or has any play they need replacement. Thanks to Matt's research I was able to purchase a pair from Amazon for $35 shipped ($15 each) a couple weeks ago very easy to replace however mine needed to get ground off as the bolts were rusted. The bushings are very inexpensive just requires a bit of time to do.

**For the record I've got a RX330 not the 400 but the suspension design is very close, as per Lexus the part number for the sway bar links appear to be the same for both cars
link -

 

thanks for the suggestion.
I ordered the same end links, just now.
I guess I could go test it first but too lazy to take the wheel off.

 

For $30 for both and that many miles they are well beyond their expiration date good idea. You can easly check the sway bar bushings by wiggling the sway bar, I did that and surprisingly mine were solid so did not replace them.

Again Matt deserve serious credit and thanks for his research, saved me (us now) almost $170 for the two links.

 

aftermath to my post.

It was the sway bar end links. It just needed regreasing (non-OEM end links)
While it was possible suspect from the start, when i shook the car by the stabilizer bar, nothing moved. Hence, i thought my sway bar end links were good.
I even reseated the rear passenger brake pads and re-lubed the slide pins (semi-"dry"), and greased the pad contact points. No change in the sound.

Anyways, i was about to unhook the endlinks for a test drive but i didn't have the right socket (15mm or 9/16) because mine was a Moog replacement. I don't even remember when I changed it: Either ~9 years ago by me during strut replacement, or someone else must've changed it in the last 4 years while i was away. Anyhow, i found out Moog has a grease refill insert built in. Bought a $15 chinese grease gun and grease from amazon and refilled the grease. Zero noise.

Couldn't believe it. I swear when I shook the car, and it made the clunk (not every time), it was closer to the upper shock mount area. The sound wasn't coming from the brake/lower strut area, i swear!! Anyways, the car is super quiet, but I'm going to regrease the front end links, also.