Hi All,

This is most likely a shot in the dark, but we own a 2016 RX350 AWD with 55K miles. Over the last year or so we have developed a frontend clunk, mainly on coming from the left side, occasionally on the right. This clunk only happens at lower speeds on really bumpy or uneven roads. After months of research, I proactively replaced the sway bar end links as this looks to be a common weak point on Toyota products. However, that did not resolve the issue. I also searched Toyota highlander forums as the platform is identical to the RX but have had no luck. I figured I'd try on here to see if anyone has experienced a frontend clunk and resolved it?

My next step would be to replace the struts and top hats to see if that resolves the noise. I'll keep you all posted as this can help others in the future.

Thanks

 

We have a 17 with 62k on the clock no clunks.

 

Just an opinion from experience on other cars, I would suspect the struts, particularly the crown bearings. Good luck with it. Please let us know if/when you find a fix.

 

I have a clunk, driver's side front. It only happens when the car is cold, backing out the driveway with steering wheel cranked all the way.
Dunno what the heck it is.

 

I advise anyone complaining of a clunk when cold on turns, especially in and out of driveways or changing grades of surface to check the sunroof seal. It can be done by driving the route it makes the noise during, ie backing out of driveway, while applying slight upward pressure to the sunroofs glass panel. You can feel the clunk in the glass if you hold it lightly and eliminate the clunk with some upward pressure, opening the sunroof full should eliminate the noise altogether, not a fun or plausible thing to do in snow and ice, you’ll need to wait for a day in the 40’s to avoid frozen sunroof linkage or damaging the sunroof motor. You would not think it is capable of producing the clunk it does. I replaced the seal on my 2014 ES350, fixed my clunk. Frank

 

I had clunks on my 2016 and they came from rotors. There was antiseize between rotors and the hubs that caused the rotors to rotate a bit and contact the wheel studs. Dealer cleaned the antiseize and torqued the wheels to spec. Clunk is gone.

 

That's a good callout. I'll take a look. I believe we're on the second set of brakes.

I keep racking my brain and trying to think outside the box. It's hard to believe that a Toyota product would develop suspension clunk this early. I need to check the sunroof as well.

 

Figured it out.

It's the sunroof glass. The glass itself has the slightest play. To validate, I stuck a detailing towel between the headliner and glass, then drove around on the same route - no more clunking. Also searched "Lexus Sunroof Rattle" and found several threads on older RX's having similar issues as well as GS350's from the same period. The permanent fix is to install a new seal around the glass and based on videos, it looks relatively easy to do. I'll keep you posted.

In addition, while sitting in my driver's position, the part of the sunroof that rattles is directly in front of my face. This makes sense now that I thought it was coming from the LF suspension.

 

Tracking sound direction in a vehicle interior can be a maddening exercise. Glad you figured it out and it has relatively easy fix.

 

I was surprised that my noise was in fact the sunroof as well, it was in the maintenance history report the dealer supplied when I bought my ES350 last January at Lexus of Winter Park, Fl. The customer declined the not covered under warranty repair, the dealer quoted them around 400 bucks to replace the seal. I was able to confirm this was the problem road testing the car before purchasing it. I bought the seal, a cabin filter and air filter, also declined repairs, from an online Toyota Dealers parts department. It was a bit tricky getting the sunroof panel oriented, I unbolted just the front 2 torx bolts after raising the rear of the sunroof, that made seal replacement pretty simple, aligning the dots at each corner and there is a mark at the rear of the seal and sunroof to align also. I had to perform a minor adjustment when tightening the torx bolts, the accordian weatherstrip on each side was a bit of a pain to reinstall but I got it all back together and my noise was gone, the car was also quieter on the highway as far as wind noise leaking at the sunroof panel. I own a fair amount of snap on tools, sockets, etc. I highly recommend a newer quality torx socket for removal of the screws or you will round/strip the retainer bolts for the sunroof panel, just my 2 cents on that. Frank

 

Good stuff. I stuffed a detailing towel in there for now and its amazing how quiet the car got. I plan on pulling the whole panel out and just doing the seal on my living room floor. What size is the torx?

 

The torx size is T25

 

Thanks for this tip. I’ve had clunking at low speeds over bumpy terrain going on for about a year in my 2017 with 70k. Mechanic couldnt find the exact source and said all the struts, bushings, etc looked good and safe to drive. I even tried padding my spare tire thinking it was coming from there.

This is the first place I’ve seen the sunroof glass panel mentioned. I wedged a couple microfibers inside the headliner against the sunroof at the very front like another post said. Drove it today and the clunk is gone for now. Thanks!!!!!!