pot_head

hi. when i go over a sharp bump i can hear some clunking sound coming from the rear. if you go slowly over the bump theres no sound. like going over manholes and stuff, theres no clunking,, but when going over potholes or large crappy expansion joints theres a clunk or two. runflats or supsension prob? maybe its the screen in the trunk? thanks.

Exhaloprez

I have the same problem. You described it perfectly. My car was manufactured in Sept. 2001 so it had the updated suspension adjustments/bushings. I can only assume it is the tires which I will get rid of. At the 5,000 mile service (in two weeks), I will press Lexus for an answer.

LexusSC430

Nope not the tires at all. I have 19" Pirellis on the car and for some reason here in Jersey we have what look like speed bumps on the highway. So when the rear wheels hit these bumps doing a good speed, you hear the thump. I can only assume its the suspension maxing out or the tire hitting some plastic or something. Doesnt really bother me though..

pot_head

i see those older hondas, toyotas, mazdas and stuff like that clunk and rattle when they get older. my car only has 4000km on it and the rear is clunking already. if there is a sharp bump about 1-1.5" high and im doing 40miles/hr, i can hear a rattle, not a thump.

i also have a 87 mazda rx7 with 170000km, and it also does the same. HUH?????? WTF??? somethings not right? unnless the Lexus is just another japanese car which i hope im wrong.

i also have a 94 BMW 325is. i changed it to Jamex shocks/springs when it had 40000km. now it has 75000km and the car doesnt make a sound at all.

so what gives? overall, i love the car but im really dissapointed about the clunking in the back. gotta take it to a dealer i guess.

HighROI

I posted a note about this problem with my October manufactured SC430 in December after having read similar postings from others. Here is what my service rep. reported when I brought the car in for its 1000 mile check up. "Road test for harsh clunk in rear suspension over bumps. Confirmed noise and special ordered parts". They replaced the bushings (an all day job) and the problem is no longer. Don't assume a later production car will be without this problem. If the rear end "clunks" over RR tracks, potholes, etc. have it checked out - you don't want to live with it, believe me, new bushings make a big difference.

therocker

Absolutely, I had the same procedure performed on my SC 430 a couple of months ago (replaced rear bushings) and does indeed make a difference.

Carnut

I had my car in for the update and at the same time changed the runflats for Pilot sports, car rides great and even with the Phila area terrible roads, I no longer hear a thing.

Exhaloprez

Are the last four numbers of your vin no. 9063 or higher? I have been told that those cars had the bushing retrofit during production.

HighROI

Exhaloprez-

Your source's supposition about the suspension problem being more problematic on VIN #'s below 9063 fit my car's (VIN # 8292) condition (which was recently corrected as noted above). I wonder what percentage of car's produced (below VIN #9063) have that problem? It would be a shame for many uninformed SC430 owners to live with bad bushings thinking that the runflat tires are at fault. I can envision some owners replacing those runflats earlier than they would have otherwise (if at all) believing the tire change solves the problem.

LexusSC430

ehhhh...It doesnt bother me much if that is the case. Im not one to complain. I guess paying 63k for a car would entitle you to such a complaint, but a thump every now and then is not going to make me send the car back. I guess I would rather leave the car as much as "factory" as possible. I just dont like when people take the car apart, because remember there are always extra screws left over.