Clunk Sound In Rear - The $15 Fix

[branshew]

I think that I have posted about this before after I did the repair on my '95, but I think that this will be beneficial to put it out there again since I can now confirm that it is a multi-generational problem. I have had this same problem on my Gen2 and Gen 4 ES300s and my mom had it on her Gen 3.

When going over uneven pavement, I would get a clunk sound from the rear suspension. It started around 150K miles on all three vehicles, but YMMV. It's not a rattle or a squeak and usually it is a double clunking noise. I noticed that the sound would not appear when both back wheels went over the uneven spot simultaneously (like a speed bump or the dip at the end of my driveway). I will also say that after 150K miles, I am still on my original struts. I had the car at the tire shop getting a new set recently and they commented that I should have my struts replaced due to the clunking noise in the back. They still work well, aren't leaking, and rebound without bouncing so I haven't had the need to replace them. Some strut manufacturers will have you believe that you should replace your struts after a specific interval - that's BS.

If you have this problem, replace your sway bar bushings. For those of you not well versed in suspension, the sway bar is a solid metal rod that runs across the width of the car linking the rear struts together. It is attached to the struts with sway bar links and it is designed to improve handling by keeping the struts aligned and decreasing body roll in corners. The sway bar is attached to the body by two brackets (one on each side) and inside each bracket is the rubber bushing that surrounds the sway bar and keeps it from knocking around. The sway bar is designed to slide back and forth in a controlled fashion inside the bushings. When the bushings age, the natural lubrication properties of the bushing material dry out and there is more friction against the sway bar so it can't slide as freely. When this happens, it binds momentarily and then releases, thus causing the clunking sound. The double clunk is caused when it moves in one direction and then returns back to normal, binding both times.

The set of two for the Gen4 cost me $6 from partsgeek and shipping was $9. (This was a couple of dollars less than the local Lexus dealer and I didn't have to go out of the way to pick them up). I think that the Gen 2 are larger (and may cost more) and they are ridged on the inside. The Gen4 are smaller and smooth inside. On the Gen4 I had to remove 3 bolts on each bracket and then I could remove the link. Gen2 was only 2 bolts. I sprayed a little lithium grease on the bar and put the new links around and then put the bracket back on. Total was less than 30 minutes. The Gen2 is easy to access without lifting the rear. I did the Gen 4 tonight while it was on the ground without my ramps (out on loan) and it was cumbersome, but doable. If you're not the wrench turning type, have your mechanic do this before replacing anything else.

Apologies for not taking pictures or providing a more detailed write-up on this procedure, but it was getting dark and I was in a hurry. If I get motivated I may add them later.