peterls

So, I hit a stupid curb that is really badly placed (tons of tire marks on it) but luckily the curb was not high, and then I hear this metallic rattle like when you put a ruler over the age of the desk and pull on it and it rattles like the diving board in a swimming pull... very fast rattle, and I felt a bit of a vibration in the steering wheel as that was going on, and it took maybe even two seconds to fully settle. Something felt too loose definitely.

That did not feel right, so I am wondering if anyone here has any clues what it could be?

I had a mechanic who used to own the same 1st gen ls400 like mine put it on a lift before this happened, and all he said was that right upper control arm is due for a change, although not terrible yet...

Could it be just the UCAs then?

Another thing, don't know if it is related: but my right rotor is warped, and sometimes it produces more vibration sometimes less, depending on the speed and whether the road is perfectly flat or not. If it is bumpy, brakes vibrate lots more, but on a nice smooth road, it is not that bad. It is also quite bad on downhill.

UCAs or something else? (and rotors obviously)

Shmee

iTrader: (3)

If you want guesses, anything in the front suspension could cause that. From a loose bolt to a worn out joint.



Get the front in the air and start checking it our. Look for my coilover how too thread, I posted a video of how to check ball joints that is far more definitive that the ol shake test.

PureDrifter

iTrader: (10)

lol you hit a curb, no idea what could be the problem until you get the wheel off it and see what you broke.
Could literally be just about any part of the front suspension depending on how you hit it.

peterls

I don't think anything is broke, it would take quite a hit, and I was only doing 25-30mph and the curb is only some 4 inches or so... but something's definitely loose.
I guess I will replace the UCA and see if that improves things first. I looked underneath myself, and could not find anything loose, even bushings (that I could see) seemed fine.

Shmee

iTrader: (3)

Why not check things out rather than replacing stuff for the sake of hope? Unless your UCAs are questionable to begin with and you wanted to change them anyways, of course...

peterls

Yeah, UCAs are bad, so they have to go anyway, just didn't think they would be the culprit in this case, but maybe they are... its just so damn hard to tell what it could be, it all seems rock solid. Maybe that noise was normal?

Shmee

iTrader: (3)

Hard to tell? What tests have you done to check?
Are you getting conflicting results or none at all?

peterls

First there was a professional mechanic who just happened to own this exact same car (1990 ls400), and he said I only need new UCA - he just tested it while it was on the lift, by pushing the wheel with his hands.
Then I looked again on my parking, and nothing else seemed to move (I got underneath it so I could not see as well as he could)

Shmee

iTrader: (3)

Use the method i posted in the coilover how to.
it's easy to find worn out joints.