Suspension calibration

[Sirdread Lurker Find all posts View Profile Close Sirdread]

Hi All. I own a UK spec LC120 LC5 (Grande). The adjustable rear suspension all operates as it should Increasing around 30mm between each settings. However I went out at the weekend and measured it all as I have never been truly happy with its normal operating height as I feel the rake from rear to front is too great.

So on normal setting the rear sits nearly 80mm higher than the front and when switched to high increases to 110mm difference. Reading on this forum the difference typically on a standard car is around 30mm higher at the rear from what I have read.

My questions is how do I lower the normal height by 50mm at the rear. Is this something that can be done via techstream and DIY or is it Toyota dealership modification only

Any help appreciated.

P.S. Great forum .

[Guest Close Guest]

What is the front and rear suspension height? Measure from bottom of the wheel to the wheel arch.

By the height difference you are quoting, either the front has sagged a lot or someone has adjusted the rear height sensors.

What you need to do will depend on the suspension height measurement.

[Sirdread Lurker Find all posts View Profile Close Sirdread]

Many thanks. Will measure tomorrow and post back.

[Sirdread Lurker Find all posts View Profile Close Sirdread]

Right. Engine running, nothing in the boot, in normal position
Front - 735mm
Rear 817mm

[Guest Close Guest]

The front looks normal. The rear has been adjusted previously. Do you have any knowledge of it?
Get under the rear, on top of the axle and look for something like this.


When a lift is done to a Grande, the height sensors are packed out with washers like this (see middle of photo):


Can you take photos of both height sensors and post back here? If you don't find spacers like in the 2nd photo, and the adjustment is in the middle position of the slot like in the 1st photo, then you may have something else bent/damaged. Have you had any impacts to that area?

[Sirdread Lurker Find all posts View Profile Close Sirdread]

Hi. Just been underneath. Car is stock , never been lifted and to my knowledge never had a bump or at least no record of it. There are no spacers on the sensor mounts and the adjuster is in the middle as in your picture.

[Guest Close Guest]

In that case, loosen the nut and lower it down the slot. Take care when loosening as the sensor is fragile.

[Sirdread Lurker Find all posts View Profile Close Sirdread]

Any suggestion on how much ? Couple of mm or 10mm or is it just trial and error till I get it near the 760 mark ?

[Guest Close Guest]

All the way down at the first go. Your aim is for 780mm. It is approximately a 3:1 ratio. So 1mm adjustment = 3mm change in height.

[Sirdread Lurker Find all posts View Profile Close Sirdread]

Many thanks. I will make some adjustments over next couple of days and let you know how it goes. Appreciate your help.

[Sirdread Lurker Find all posts View Profile Close Sirdread]

So I have undone the nut, moved the arm down to the lowest point and retightened the nut. Cycled through the suspension heights, taken a very short drive and there is no change to the ride height at the rear.

Any suggestions

[Guest Close Guest]

That's odd. The adjustment isn't making any difference. But yet, it knows when to stop inflating/deflating?
Wonder what happens if you totally deflate the airbags and then start the engine? You'll need a special service tool (SST) to pull the air tube out of the compressor output port to deflate the airbags.

[Anth120playdo Banned Find all posts View Profile Close Anth120playdo]

I have found the adjustment to do very little & nothing.
I gently manipulate the rework able bracket the sensors are mounted on (bend it).
The front should be 750+, it probably has a Bullbar.

[Sirdread Lurker Find all posts View Profile Close Sirdread]

Will have another look underneath. There is no bulbar on the car

[Sirdread Lurker Find all posts View Profile Close Sirdread]

So last night I did a bit more playing with this. I undid the nut and moved the arm to the top of the bracket and that did raise the car by a further 15mm in normal mode. Is it worth reducing the rod with the pivoting ends as this does look to be adjustable ?

If I completely undo the arm from the bracket and start the car what suspension height would it set to as I am assuming the sensor stops moving the arm when it gets to the end of its travel or meets some kind of resistance ?