I appreciate the issues we can have with our suspension can start to drop overnight.

Over the past month my vehicle has done this twice - but is fine other wise. My thought would be that if there was an actual issue the suspension would drop all the time.

Now I have my suspension at 20mm below onroad height so as standard is about mid way between access and onroad height. I have also noticed that when the suspension has dropped it has been warm during the day (15 degrees C) when the car was parked up but at night the temp dropped to -5 degrees C. As we know when air cools it reduces volume so my simple question is:

When just above access height is a temperature drop of around 20 degrees C in 12 hours with the car parked and outside enough to reduce the volume in the suspension system to make it drop?

As said this dropping is not regular so unlikely at this stage to be a leak as it would be happening all the time.

Thanks

Garry 07MY RRS TDV6
Arctic Frost
Aspen Interior

Are your tyre pressures also going down so markedly over night with the temperature drop. The air in them must also be contracting equally? 2020 Pangea Green 1st Edition D240 New Defender 110 is here and loving it
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I would assume so - you should always check tyre pressures when they are cold as warm tyres can be be quite a few PSI higher than cold tyres with the same amount of air in them.

Not sure if you have it in the UK but we use the 4psi rule here - covers onroad and offroad use. Basically tyres in use should not increase by 4psi when hot compared to cold. If the increase is more than 4psi for the conditions then tyre pressure is too low.

But is a another topic.

Garry 07MY RRS TDV6
Arctic Frost
Aspen Interior

Do you have any air leaks from the compressor - does it go up and down ok - no over run?
Check the panels under the car - the box that conceals the compressor for any damage and the air reservoir too

Also look at all height sensors on the screen - are they OK or blinking red?
Physically check them out too incase they have rotted or deteriorated in anyway

Is where you park level ground?
Any warning signs as you start the car

Thanks for that check list - there are no adverse indications anywhere.

I had a third drop the night before last. I started yesterday morning and the car was down. I drove and then parked the car at about 10 yesterday morning and it has not moved since. I checked the the car at 1 this morning and still up and again when I got up this morning and it is still up.

So as the drop is intermittent I dont believe it is a leak as such, ie a connector leaking as the suspension would be dropping all the time. Is the valve that lets the air out when you lower the vehicle likely to be playing up on an intermittent basis. Can it operate by itself when the car is asleep and wakes up to do its checked.

Also of note, the car only drops at night, never during the day.

Garry 07MY RRS TDV6
Arctic Frost
Aspen Interior

I have replaced the battery in my car as the old one was just about dead - since then I have not had a suspension drop but it is early days.

garry 07MY RRS TDV6
Arctic Frost
Aspen Interior