Notquiteadisco wrote:

Yes all the vehicles involved are air suspension and all have a form of adaptive damping.

alex0264 wrote:

1784 wrote:

As mentioned previously, there are no electronics involved in the ride quality of a D3/D4 as long as the air suspension heights are correct (which has been confirmed they are).

You could create another scenario - imagine a fault develops in the ride level control module itself, which causes the entire EAS system to dump all air, from the springs, the reservoir, the whole lot. The car is then going to be down on the bump stops and quite literally bouncing down the road. Are you saying that this would not be an electrical fault causing poor ride quality in that scenario.

1784 wrote:

alex0264 wrote:

1784 wrote:

As mentioned previously, there are no electronics involved in the ride quality of a D3/D4 as long as the air suspension heights are correct (which has been confirmed they are).

You could create another scenario - imagine a fault develops in the ride level control module itself, which causes the entire EAS system to dump all air, from the springs, the reservoir, the whole lot. The car is then going to be down on the bump stops and quite literally bouncing down the road. Are you saying that this would not be an electrical fault causing poor ride quality in that scenario.

As I wrote above, the electronic module does manage the ride height through airbag pressure and selecting different heights will affect the ride quality. But that is also the only control it has, and as you mention the affected vehicle sits on normal height, then that's it when it comes to electronic control of the suspension. Once the requested height is reached, the ride quality is up to the air in the bags and the conventional dampers, bushings and tyres.

As you doubt my explanation, please check LR's own description in the "Description and operation" of the Vehicle dynamic suspension section in the manual available on the sites wiki page.

1784 wrote:

Notquiteadisco wrote:

Yes all the vehicles involved are air suspension and all have a form of adaptive damping.

Which LR models are these with adaptive damping?

itsaguything wrote:

The workshop manual is a fantastic read for those interested in learning about the air suspension system on the disco4. For comparisons sake, have a read of the xjr and xkr workshop manuals.
Yes, different forms of dampers are available for some vehicles. The XJR and XKR use examples of this adaptive and dynamic technology thus adjusting the dampening rate as necessary, dynamically or manually.

BUT such dampers are NOT installed on a disco4. The air spring is strictly designed for ride height changes. There is no active dampening circuit or pathway to adjust “ride quality”.

What I have seen and sadly experienced are some who install LT rated tires on their vehicles, inflated to setting well beyond what the disco4 was engineered for.

Cheers to all.
G.

itsaguything wrote:

hmmm, maybe... I have no experience with a worn damper causing a firm ride. A bouncy ride, absolutely, but not a firm ride.

Cheers to all!

alex0264 wrote:

There were a couple of bits I meant to add before signing off from this thread, so I will add these below.

For anyone else trying to diagnose this issue, have a think about whether there was any kind of 'event' that occurred before the ride went bad. Was it a gradual thing, or did you drive the car one day and suddenly it was bad.

My 2014 HSE was fine until I hit a nasty hole in the road on the O/S/F corner, and it starting getting rough after about a week of driving after. Bushes and shock absorber were not damaged.

My 2015 HSE Lux was fine until the battery failed in spectacular fashion on Christmas day - when attempting to start the car it went bonkers, the needles on the clocks were jumping around, the lights were stuck on and I had to abandon the car. Since then that is when the ride quality started going bad. I should also add that the garage I bought it from pressure wash their engine bays before sale. I know Land Rover's are supposed to deal with water, but in my opinion blasting high velocity water under the bonnet really isn't great.

Hope the above might help slightly, just wanted to add those bits.