SaintNexus

Hey guys

Two days ago I got my Lexus LS400. Its brown/burgandy, its 1990, and has 130k miles (im a bit suspicious of it, but the carfax shows clean title, clean history, etc.)

So, anyway. I noticed that there are height options. That goes from Lo, Norm, or High.

Next to the drivers seat, I see the options Norm and High, but how do i get the car to go Low?

Kansas

The suspension of your 90 LS automatically lowers to the low position at highway speeds -- don't remember the speed at which it lowers but you should notice when it lowers. Attached is the relevant page from the 90 LS owners manual. If you don't have a copy, you can view it online on the Lexus website and order a free paper copy of it.

The system does not allow manually lowering the suspension to the low position -- possibly to prevent damage to the car.

SaintNexus

How fast do you need to be driving for the cars suspension to go to Low mode?

Also, I noticed an Over Drive button, or something like that. My dad told me that I press that once I'm going over 55mph, but I doubt he's right, and I have no idea what that button is for.

Brandicus

iTrader: (6)

your dad is spot on, overdrive will downshift the car from 4th gear to 3rd for quick passes on the highway

Kansas

I don't know if the speed is documented. I think it is something like 55-60 mph. Like I said, I think you will notice when the car lowers slightly. Back in the early 1990's when LS400's with air suspension were more common, it was obvious when driving along side another LS400 when the other car's suspension lowered.

Leave your overdrive on all the time unless you occasionally need extra power while pulling a trailer or increased engine braking in mountain driving. I doubt if I turned overdrive off more than three times in over 13 years of driving a 90 LS. Treat your transmission as what it really is - a four speed transmission.

Overdrive is sort of a misnomer these days. Almost all modern transmission are "overdrive" transmissions in that the ratios of 4th, 5th, 6th, etc. gears allow the output speed to the drive shaft to be higher than the speed of the rotating crankshaft.

From the 1930's or so until the 1980's on some cars, overdrives were separate two speed transmissions that were mounted behind an automatic or manual transmission and usually operated with a switch on the shift lever. Shifting into overdrive used to always be a manual operation that one had to do intentionally. True overdrives were a real PITA and usually not very reliable.

Wikipedia has a great explanation: http://en.wikipedia.org/wiki/Overdrive_%28mechanics%29

SaintNexus

Kansas, I drove up to 75, maybe even 80mph, and I didn't feel it go lower, and it didn't even say Lo or anything, it was just at Norm.

Can it be messed up? My cousins noticed that there is a lot of space between the tire and the body frame, over 3-4 inches in the front, and the car is on normal!

I think the suspension could be messed up? I'm not sure. I'll take some pics of it today and post them online though.

BLKonBLK98

if you look at the manual page posted there is no low setting. just normal and high. it will lower at speed relative to the selected mode. you're not going to notice it.

the ride height you are descrbing is normal for our cars. to go low add a data systems controller.

SaintNexus

So its normal for the front tires to be about 4 inches below the body frame? That just seems to be a bit too much.

If I decide to drop my car about 3 inches, will the air suspension still work if I choose the High setting, to get the car to go up a few inches?

This way, I can have my car low, but when I get to speed bumps or broken roads, I can raise it to not have damage done to the body.

jmblimo

iTrader: (1)

My '92 drops to low at about 83mph. You have to be careful of the police at that speed!

PureDrifter

iTrader: (10)

the bags WILL blow rather quickly if you drive them at anything lower than stock height using a controller.

SaintNexus

Ok, so if the bags will blow if I drop them, should I just get big wheels then? But then, it'll probably look ghetto or something.