marksa

2010 Lexus RX350 100k miles...

Rattle or clunk clunk in front end when driving on bumpy areas.

What is this noise? I've recorded it here:
* I've replaced the ball joints (not the lower control arm though)
* Doesn't seem to make noise in the struts when standing still and pumping the front up and down, the struts actually seem secure.

Any help?

chuyrobles

I would check the strut mounts (the bearing on top) and the control arm bushings.

marksa

Thank you for that.

How can I check them? I'll Google online for this too.

I feel like I'm chasing ghosts at this point, don't want to just replace parts without a reasonable claim that it is the problem at hand

chuyrobles

Strut mount - With the wheels off the ground, grip the coil spring as close to the upper strut mount as possible. Push in and out on the strut and spring while watching for movement of the upper end of the strut piston rod. There should be no free movement.

Bushings - with wheels off the ground, use pry bar to attempt to move the control arm; it should not move.

Edit note: Hadn’t seen the video till now, also sounds like something is loose. Go under the car and check that nothing is loose.

rx450h415

There's nothing really you can do to 'test' the strut mounts or bearings.
mine were making this noise

others made a different noise. you can see if the center bolt is rubbing on the upper strut mount.

if it were the lower control arm, you could make the noise with the car jacked up and wiggling the tire.

i changed my strut mount bearings, and there is definitely something in there that causes noises even tho it seams unlikely as it fixed my noise. it also makes other noises besides the video i posted.

marksa

Thanks for that.

This car, no noises when turning the wheel. Cannot replicate the noise on the jack stands, or when the car is sitting still. Can only seem to replicate the sound when driving.

Same noise whether the car is in gear or out of gear.

So with your video, I'm expecting my noise is likely not the strut mounts?

marksa

A few folks have suggested it could be engine mounts.

In checking the engine mounts by reving the car while stopped, the engine does move but there are no clunks. Also, the engine does not appear to move any more than a few other cars we looked at at the same time.

What are your thoughts?

Clutchless

This is almost impossible to diagnose over the internet. It really needs an in person inspection by an experienced, qualified and honest mechanic. Find a well regarded local independent asian car repair specialist shop.
You may just need to replace the front struts, strut mounts and strut mount bearings after 100,000 miles, or worn control arm or other bushings or even a motor/transmission mount, but as stated, a qualified honest tech needs to inspect it.

If you need to find a good local repair shop start by searching on this site of shops recommended by listeners of the old car repair radio show, Car Talk. You can enter your state and also city.
Then cross check any potential places on Yelp or Google for more current info. https://www.cartalk.com/mechanics-files

rx450h415

all of this is true, but if you work on cars and have air tools. i would change the strut mounts yourself.. if you don't have air tools or an electric impact you can still doit but its gonna take forever. especially when using spring compressors. you could sit there with a ratchet and turn that spring compressor forever. i used 4 spring compressors.
the strut mounts are very inexpensive. taking it to a mechanic could cost you several hundred just to troubleshoot. my rx had 100k and changing the strut mounts fixed it. also check your struts for any leaks. if the struts are leaking its time to change them. i had a noise on one side of another car(bmw), and i saw fluid all around the strut. changing the whole strut fixed that situation.

Clutchless

Reviewing your suggestions, and considering the diagnosis costs, it appears to me that it may be best to replace the front struts, strut mounts and bearings first and see if the clunk disappears afterward. At least the car should drive and ride better afterward. With that many miles I would not just replace the strut mounts.

Lexy54

That sounds a lot like my 2011 power steering rattle when you go over bumps. Had the noise start out noticeable but softer and eventually got quite annoyingly loud. Didn't start out having the noise when turning the steering wheel quickly side to side 1/2 rotation starting out with a straight ahead steering wheel, but eventually that became noticeable too. Although turning the wheel was not near as loud as when going over bumps. Sounded like it was coming from the front end under the car but I could never find it until I saw a TSB from Lexus L-SB-0026-11 "Some 2010 – 2011 model year RX 350 vehicles may exhibit a rattle noise from the EPS (Electric Power Steering) Column when turning the steering wheel and/or when driving on rough surfaces."

You did say that you don't have a noise when turning the wheel so that issue may not be it. The TSB gives a VIN range for the issue so I would check to see if yours falls within the range just to rule it out. Turns out it is a bad design using an internal rubber bushing that degrades over time alIowing metal-to-metal contact in the PS unit making the rattle noise. I was at 84,000 miles when I saw the TSB which put me out of warranty for a fix. Lexus dealer wanted $4000 ($3000 for new PS unit and $1000 labor) to fix it. I contacted Corporate Brand Engagement Center and they offered up to $1500 as help for fixing it. That's nice money but not even half the cost of the poorly designed PS unit. I declined as it was just after my having a failure of the notorious oil cooler rubber pipe leak. I have lost faith in Lexus design engineers.

tempestv8

In my case, it started to happen a few days after I had a steering wheel alignment done.

Turns out that the tech did not tighten the adjustment nut on where the tie rod end is attached to the steering rack! I could turn the nut with my finger!

Not saying that this is your problem, but worth checking, just in case!

rx450h415

Have you checked the sway bar links to see if they are loose? i replaced mine and didn't tighten them all the way.

szukalaster

There sounds like two noises. A suspension part and the bushing that goes between the steering motor and where it sits. They break apart and sound similar. If you shake your wheel left to right powered on you can hear it rattle from under the dash.