Clunking sound over bumps (Ball Joints or Bearings?)

[rollinginmyLS400]

Hey everyone. I own a 1992 Lexus LS400 with 135k miles on it. It is in beautiful shape but it has started to experience some issues with the suspension. I converted the original air suspension to normal struts about 2 years ago and about a year ago replaced the lower ball joints. However, the past year or so I started getting a clunking/popping sound when whenver I go over a bump or am on a bumpy road.

I have gone to several mechanics and some tell me it is the upper ball joints/control arm and others tell me it is the bearings causing the sound. I cannot seem to get a straight answer on it. And...they are both very expensive problems to get fixed. I do not want to just start dumping hundreds of dollars on a 17 year old car towards a problem I do not even know is the issue.

Is this sound/problem consistent with Upper Ball Joint issues or Bearings...or both? Is their a way I can investigate this myself to know for certain?

If it is both an issue, is this a job a relative rookie mechanic like myself could work on? Does anyone have step by step directions for a job like this.

Thanks everyone!

 

[cjsupra90]

I highly doubt thar it is a bearing.. You would have gotton a grawling noise long before you get a clunking noise and that grawling would be extremely nasty sounding if the bearing was far enough gone to make a clunking...

Can you tell what side its comming from? If so, then jack that side up, take the wheel off and check for looseness in all the different suspension items.... To check the Ball Joints, with the lug nuts holding the brake rotor on fairly tightly, brab the top and bottom of the rotor and try to rock it back and forth.. If you there is play or movement in the spindle but not in the control arms, then its the ball joint(s).. if the control arm seems sloppy or loose and moves with the spindle, then chances are its control arm bushing... Also make sure to check where the sway bar (anti-roll bar) attached to the frame and make sure that the bracket isn't broke and or the rubber bushing isn't badly deterierated or gone. Also check the links that link the sway bar (anti-roll bar) to the lower suspension to make sure that all that is tight and not broke or anything....

 

[cjsupra90]

Oh, one question, is the clunking not present when braking on bumpy road or when ever it would normally cause the clunking to accure? If the clunking is not there while braking, then I would also possibly suspect a problem in the brakes, either pad loose in thier seats in the caliper bracket or excessively worn sliders thus allowing the caliper to raddle and move around...

 

[rollinginmyLS400]

Thanks for the reply and the info.

First off, the clunking/popping sound is coming from both front sides although it is worse on the passenger side than the driver side.

It does not happen when braking, but only happens when you hit like a manhole on the road or a bump in the road. I recently got the brakes done on the vehicle (rotors and pads) and the problem was there before and after the brake job so I know it is not that.

Is the control arm bushing and sway bar expensive?

 

[rollinginmyLS400]

One other thing...I have had the car for over 4 years, and it does not seem to be handling as well as it used too...and the car cannot seem to hold a good alignment.

 

[cjsupra90]

Well being that the handling seems to have changed and wont retain a proper alignment, then this goes back to suspension......

Control arm bushing might not be avalible without buying the whole control are.. I think the same goes for the upper ball joints.. If the control arm bushing are avalible, then they usually range between $10 and $20 per bushing... They can be a PITA to change as they are pressed in.. If can be done with a big vise, but an actual hydraulic press make life much easier...

I would still get it up in the air and just start checking things... You could possibly have a combination if issues due to age and milage plus if the car is driven in CO. winters, then Im sure you have bushing on thier way out cause the rubber doesn't hold up will to the salted slush coming from the roads in the winter...

 

[rollinginmyLS400]

Thanks for the advice. The car spent most of it's life in FL, which is where I bought it. It has only been in Colorado for one winter so far.

But yeah, I have a feeling it is a combination of things. I will get under there and check it out and let you know. I can do some work myself, but I am afraid this job might be a little over my head.

 

[tsirovy]

Sounds to me like the sway bar bushings. I had to replace these on my 96 when i first got it. One of the bushings was torn and the sway bar was hitting the frame metal that it goes through, over bumps and had a loose handling feeling.

 

[rollinginmyLS400]

Thanks for the info everyone. Are sway bar bushings expensive? And how hard would it be to replace them myself?

 

[Da Coupe]

Sounds like your strut bar cushions are worn. I don't know how to post links but just google "LS400 strut bar bushing replacement" and look for the Lextreme link. It should be the first one. There you'll find directions on replacement. Funny, I searched here but nothing came up.