I get a rattle noise over rough roads, turning over curb not speed bumps..Sounds like its coming from right in front of me while driving towards bottom..Ive replaces shaft,ball joints,rack bushing and tie rods..Im about to do the control arm bushings..2 mechanics said everything looks good underneath..I also noticed if im parked and rock wheel side to side i hear a thump but i dont hear it while driving..Any help?? Thanks

 

Does not sound like it is suspension. This would not transfer through the steering as you described. Bad arms mainly give you clunks over rough road. Did you make sure to torque the rack properly? Have someone verify the rack is not moving as you turn the wheel back and forth with tires on the ground. If that is good I would throughly inspect the column itself. I don't remember if there is another bushing in there or not. I would also make sure any obvious bolts are tight on the shaft assembly to the rack.

 

I went to a nascar race one year and had to park on gravel. Driving over it at 15mph gave me the worst rattle ever out of any car I've ever owned. I did the steering rack bushings and it helped, but I haven't been back in that situation since. If you find it to be something other than steering rack bushings or strut mounts please share!

 

Take a look at service bulletin ST001-04

Universal joint replacement in the steering column.

I'm about to do this to my 98 LS400. Bulletin includes my car in this range.

See this thread for my documentation + audio recording:
https://www.clublexus.com/forums/ls-...-bushings.html

Posting this here to provide future reference to others.