My car has 55 profile tyres on so the car is a little higher than stock.

I have an IID and thought I would lower the height a bit, maybe 10-15mm, but will this have a negative impact on the ride quality?

Cheers

10-15mm shouldn't be too bad. Key thing will be that the car is nearer the bump stops - so don't expect it to ride speed bumps as fast as before without bottoming out. Paul,
2001 Discovery 2 TD5, 211,000 miles & climbing
2006 FFRR TDV8 Vogue 151,000 miles & now sold
Member of Midland (Land) Rover Owners Club, www.mroc.co.uk

i lowered my old SC by 10mm and had no problems.. ... - .- -.




Y. O. L. O.
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when my rangie was bought it was one of the first things i done 16 years ago looks better the ride smooth and save fuel being lower

How does it save fuel out of interest? 2009 (2010 MY) 5.0 Supercharged Autobiography
2007 TDV8 Vogue SE
2005 BMW E63 645ci
2024 Porsche Macan

(How does it save fuel out of interest)

Yes my thoughts too as your still chucking the same mass through the air. Also be aware you will alter some of the steering geometry by lowering the suspension, especially the front tow settings hence why it needs to be set at normal ride height.
I did some checks, more out of curiosity TBH on the difference of the total tow setting from lowered to off road height, I was amazed at the difference.

Lowering the suspension will typically reduce underbody drag and reduce the amount of exposed drag inducing tyre hitting the air. No idea how much it would save though, but it must be enough given manufactures give the setting (or make it automatic) in newer cars for the suspension to drop at higher speeds.

Auto lowering at speed could be for improved handling too.

I sometimes lower mine by 20mm for faster twisty bends especially if there's a large vehicle tailing me as the improved handling is significant, but don't leave it down as it doesn't take much of a bump to hit the bump-stops at the front.

hi lowering the height less drag save little fuel and for me looks better

.......and there was me, thinking that being higher up enabled the cravat wearing brigade more opportunity to wave at the peasants......

To add to that, Fullfat owners talking about fuel economy Ye gads whatever next.......

He He I liked that!  Range Rover 4.2 Supercharged 2006
Ford Focus EcoBoost 1.5 2017
MG TF 2003

Previous Cars of note
Land Rover Discovery 2
Jaguar Mk2 3.8 - Company car
MG Midget 1974 - Concours

Agree. The lowering at speed is for handling rather than fuel saving, and yes does seem a bit strange talking about fuel saving in these, I just fill up and shut my eyes until it clicks 2009 (2010 MY) 5.0 Supercharged Autobiography
2007 TDV8 Vogue SE
2005 BMW E63 645ci
2024 Porsche Macan