Rear of car was seriously sagging on one side the other day...this was after the weather turned cold overnight (first time since the summer). It was parked outside overnight. In the morning, I drove it maybe half a mile and pulled over to run an errand, and when I came out and was walking back to hte car, that's when I noticed it. One side was way lower than the other. Btw, a few days before seeing this, I had been driving with the air suspension set to 'normal' as I was testing to see if a clunking noise was louder depending on the air suspension settings. I usually keep the suspension set to high. Anyway, long story short, I immediately put the suspension back on high and it's been fine every since. It's been a about a week. No more sagging. Details: The air shocks in the rear are originals -- never been replaced on a car with roughly 100K miles on it. So I know they are going to go at some point. I did put the suspension back on normal for a time and thought I did see a slight lowering on that one sdie again.

So does this mean that air shock is failing? Why would it lose air on 'normal' setting and not on 'high'?

I'd prefer to keep the air ride. I know someone who owns a repair shop and was thinking of asking if he could get me the shocks wholeslae. The company that sold me remanned shocks for the front (years ago) no longer makes them for the LS400.

I know I can convert to coil springs but if I did that the car would feel completely different, right? I realize that would be the more prudent thing to do, especially on a car this old. I just think that one rear air shock is on its last legs, tho why it holds up when the setting is on 'high' is beyond my comprehension. Above my pay grade, I think is the term.

 

If the suspension stays up when set to the high position it would suggest the strut is not leaking air or it would lose height.
It may be worth checking the height sensor which may be faulty and giving a false reading and the link rod from it to the suspension.

 

Got it. Thanks. I'll have them take a look at that sensor.

Just out of curiosity I got a quote on the shocks from a Lexus parts place I have used before -- they said $858 and change per shock. They were a grand the last time I checked, so they've come down in price in the last couple of years.