Mjdronfield I paid £450 Inc vat from Maltings 4x4 (for convience as I could collect same day) but Island 4x4 are cheapest at £410 Inc vat for BWI.

Jaygee mines running standard size 255/50/20 Pirelli scorpions.

Ffrr-lover could you do a test for me seeing as you have new rear shocks?

With your car off please could you bounce test the rear via pressing down on the tailgate/boot floor.

Is it fairly stiff or is there any give?

Mine bounces a bit so trying to work out if I could improve it even further with a pair of new rear shocks.

With the car off (last used about 3 hours earlier), I tried bouncing the car using the lowered rear tail. The car suspension is stiff and I appeared to get less than an inch of travel with my slight and slender ( ) 16st frame pushing down.
I’d say thats fairly stiff, however I am not surprised by that movement given the struts are supporting 2.7t of car and (I believe) are stiff when there is no power (i.e. they require power to soften up).

I’ve been pondering the suspension when driving my car over the last few weeks (as i am sure we all are!) and today there were a few significant large dips in the road and i noticed that the rear seemed to bounce more than the fronts, rather than both front and back bouncing the same.
Not a bad bounce, just more of an absorbing of the large weight change… whereas the fronts were more rigid.

This could just be a normal reaction to the type of bump, it could be me imaging this, or it could be that the fronts are indeed stiffer than they should be (more worn). Or it could be my head making all this st up… it certainly feels like it with teh lack of consistency!!!

I’m going with the tired front struts as that feels a likely cause of this, plus I am hopeful this is indeed the cause / fix as suggested by coopss  Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html

I know we don’t really know how it works… I’d hoped an expert might be on here….

So are we expecting that the reaction to pushing down on the rear (or indeed front) will change with the engine running?

Not sure what the default response will be with no movement inputs from the sensors.

 2011 Range Rover Vogue SE 4.4 TDV8

Previous cars :
2003 Range Rover Vogue TD6
1999 Discovery Td5 ES
1995 BMW M5 3.8 6 speed
1992 Range Rover 3.9 Efi Vogue
1992 BMW M5 3.8
1988 BMW 735i SE
1989 Ford Sierra XR4x4 2.9i
1981 Ford Fiesta Supersport

Thanks for the informative post FFRR lover.

I am of a similar weight to you and I think based upon your description that my rears might also be due replacement as from memory my rear struts move up and down more than an inch when doing the bounce test.

I'll try and enlist someone to video it so we can compare what potentially worn rear struts look like compared with new ones just for completeness.

Mjdronfield I am fairy certain the suspension doesn't become energised until moving purely based on my bounce testing but I've just received the new battery for my SDD laptop so will do some quick data logging to see if that is indeed the case

Just been out the car with SDD and I can confirm with the engine running no current is supplied to the dampers until the vehicle begins moving.

See rubbish picture of my laptop screen below:

Nice one. No point in me trying that comparison then.

If you could see/log highish current being applied whilst you drive, you could eliminate the control unit and accelerometers and pin point to the shocks.

I’d imagine if not much current is ever applied, it will always feel too firm….

 2011 Range Rover Vogue SE 4.4 TDV8

Previous cars :
2003 Range Rover Vogue TD6
1999 Discovery Td5 ES
1995 BMW M5 3.8 6 speed
1992 Range Rover 3.9 Efi Vogue
1992 BMW M5 3.8
1988 BMW 735i SE
1989 Ford Sierra XR4x4 2.9i
1981 Ford Fiesta Supersport

Mjdronfield,

Since I now feel my CVD suspension is in an operating state I will go and get a screen capture of the values when driving so that those who still suffer a hard ride can compare.

There may or may not be differences when a shock has gone 'bad' given that the shock itself doesn't report back its control blade position to the ADCM.

It would be interesting to know though.

Indeed. Would eliminate the “control system”.

I imagine on a smooth level flat straight road it might be softer… but then again it will prob go softer if there are bumps in it…. Voodoo

 2011 Range Rover Vogue SE 4.4 TDV8

Previous cars :
2003 Range Rover Vogue TD6
1999 Discovery Td5 ES
1995 BMW M5 3.8 6 speed
1992 Range Rover 3.9 Efi Vogue
1992 BMW M5 3.8
1988 BMW 735i SE
1989 Ford Sierra XR4x4 2.9i
1981 Ford Fiesta Supersport

Does it even respond to road undulations? IMO it’s just to control roll in corners and is not a ride comfort system. It can become a discomfort system when it fails though…. 2012 TDV8 Vogue (L322)

Reducing roll in corners is a secondary use of the shocks, with smoothing bumps as suspension compresses and extends their primary task. Have you noticed how the vehicle doesn't bounce a couple of times after hitting a bump, unlike non-CVDs? The valves are operated to provide a controlled rise and fall of the body.

I bought Bilstein replacements from Duckworths - the fronts about 1 year ago and the rears a year earlier.

Bilstein fronts are not as much of a bargain here than their rears. I can’t imagine there is an issue mixing brands front to back.

I thought the system was mainly to reduce body roll but i might be wrong. Think it might do more things, like soften the rears if the front hits a bump….

I can’t compare to my TD6 properly, as that had 19 inch wheels and the TDV8 20s.

I’d like to find out more about what it actually does in given situations, but there doesn’t seem to be much info on that.

 2011 Range Rover Vogue SE 4.4 TDV8

Previous cars :
2003 Range Rover Vogue TD6
1999 Discovery Td5 ES
1995 BMW M5 3.8 6 speed
1992 Range Rover 3.9 Efi Vogue
1992 BMW M5 3.8
1988 BMW 735i SE
1989 Ford Sierra XR4x4 2.9i
1981 Ford Fiesta Supersport

Last edited by mjdronfield on 17th May 2022 10:39am. Edited 1 time in total

Hi all... apologies for the long delay. I don't get as much time for forum reading and posting as I'd like!

Whilst I can't say I'm 'happy' that you guys are having suspension problems with your FFRRs, I must say I'm pretty relieved that there are others out there grappling with the same issue!

I've read through everything and I think that we're on the right track with changing the front struts - especially after Mariana's apparent success - most encouraging. I have a pair of front struts from Aerosus sitting here ready to fit (yes - the same Aerosus whose air springs leaked on my first go with them...) which they kindly sponsored to the channel. With how expensive 'proper' struts are for these, I'm willing to give Aerosus another crack of the whip and see what happens.

I too was intending to get SDD back out and do some more logging, so it would be interesting to compare data, although without driving along the same 'input' (road), it might be a bit meaningless.

Regarding accelerometers, I'm pretty sure there are only 3 on the L322 despite what the wshop manual says. I've tried replacing the one in the boot for a good used one, but haven't bothered trying to dig out either of the front ones yet. Not entirely sure where they are but it might be worth a go.

Anyway fingers crossed for all of us that the front strut replacements help all of our problems!

Yeah….. seems to be looking like front struts for most parts. When mine hardened up, it was like flicking a switch… had new rears for MOT and that changed nothing.

Interesting to see how you get on with the cheaper units. Think they have a 2 year guarantee….

 2011 Range Rover Vogue SE 4.4 TDV8

Previous cars :
2003 Range Rover Vogue TD6
1999 Discovery Td5 ES
1995 BMW M5 3.8 6 speed
1992 Range Rover 3.9 Efi Vogue
1992 BMW M5 3.8
1988 BMW 735i SE
1989 Ford Sierra XR4x4 2.9i
1981 Ford Fiesta Supersport

Dampers remove the oscillations at the resonance frequency of the suspension to avoid loss of tyre contact. If your suspension ‘bounces’ ( cvd or not) the shocks are worn and need replacing. 2012 TDV8 Vogue (L322)

I think Graeme means with 'normal' dampers, your suspension motion is a bit like the red curve, where it oscillates and overshoots the 'centre' position a couple of times before coming to a rest.

With the VDS, in theory it should be able to control the body back to its nominal position with less oscillations, like the green curve.