98 Ls400 Suspension

Jarebear · December 30, 2012

Last night I was driving my family around in my LS and it was bottoming out quite a bit at slow turns,

should my shocks be replaced? If so, I here that kyb is a good replacement for my LS, or should I just bust open my wallet at the dealer?

1990LS400 · December 30, 2012

Does your car have air suspension, non-original steel spring suspension or broken springs? The car is held up by steel or air "springs". I don't think a bad shock absorber on steel springs can cause a car to bottom out on a gentle turn. A bad air strut - if the car has air suspenstion - could cause the car to sag so much that it bottoms out.

Did you have some really, really heavy people in the back seat? :mellow: Were you on rough roads or going over rail road tracks or something similar?

Jarebear · December 30, 2012

The car doesn't have air suspension, just regular gas shocks. I think they are the original shocks when the vehicle was manufactured, and the car has just over 200,000 miles. Yea it had a couple heavy people in the car, but it still bottoms out sometimes on a turn even when it's just me in the car (I weigh 165), but it bottoms out WAY less. As a matter a fact, I can only think of one place on the road where I live where at a certain speed it will slightly bottom out on the turn when its just me or one other person in the car. You think maybe cause the suspension is so soft that when enough fat people are in it'll bottom alot? I dunno, I guess cause my car has so many miles I figured it might be time for a shock job, the springs look like they're okay.

Jarebear · December 30, 2012

the roads weren't rough, just regular streets in a suburb.

Jarebear · December 30, 2012

By the way, sometimes when I hit a slight bumb it'll make a clunk.

1990LS400 · December 31, 2012

Did you just get this car and, if so, do you know its history? My 2000 LS400 is at 160,000 miles and is virtually the same car as yours. Mine never bottoms out with a full load of adult passengers. Has your car been lowered?

The "clunk" could be a front suspension noise ... front strut bar/rod bushings rarely last 100,000 miles on these cars. Shock absorbers can last a very long time - far longer than 200,000 miles - but I suppose it depends on how much stress the car has been under.

Jarebear · December 31, 2012

yea, I gotta good feeling that the clunk noise is from the strut rod bushings. Here's a funny story, I brought it to a napa autocare center and they told me that's what was making noise, and that they'd have to get the whole new strut rod cause they couldn't get the bushing by itself, but when I checked sewell lexus parts I am able to get the strut rod bushing by itself. Also, when I went back about a half year later to get some other work done (fuel system clean, alignment, ect..) I asked again about that bushing and then they told me there were no bad bushings under my car, SAME PLACE. I took it to another place and the guy told me there's no such thing as a strut rod bushing. Either he calls it something else...or maybe he's incompetent. I haven't had it replaced yet but I'm pretty sure that's what it is. The car doesn't look to be lowered, but I'm not sure. It drives real smooth, just bottoms out sometimes.

1990LS400 · December 31, 2012

There are a variety of names for the strut bars/rods including "semi-longitudinal tension rods" -- the premature wear issue is discussed at http://www.autospeed...ms/article.html

The bushings can be purchased separately but the labor cost of having the old ones removed and the new ones pressed in can equal the cost of the whole assembly. I've read that there is an "up" and "down" side to the bushings -- be sure they aren't installed upside down ... maybe that's why some people have reported continued noise from pressed in bushings. If I remember correctly, the bushings have not always been available separately.

Now that I think about it, with a full load of passengers and a full trunk, my trailer hitch sometimes scrapes on curbs when I leave or pull into driveways - but its frame hangs below the car and the scraping is not a routine occurance.