FWIW mine has a new main battery and it is reading 12.21v at the moment having just woken the fatty up to open the bonnet...

It hasn't been anywhere for several days, just doing the worse possible and moving it 1/4 mile to the village hall twice a day as we have landscapers in and need the drive clear... Pete
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2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Just another idea. Could this “intermittent” and “worse in the morning” problem be related to moisture in the air system which affects the valve performance. Could the air dryer not be working effectively, or has moisture been trapped down stream of the drier. Moisture in the system may behave differently when cold (morning). I see the drier should “regenerate” when the airbags are lowered.
Keep in mind truck air systems have drains to remove moisture from tanks even when they have a drier.
Just another idea to think through

Unfortunately I don't have a lot of time to reply right now but I did use sdd to tell the car both batteries had been replaced, I've checked the 2 earth's related to power steering (according to an old TSB) both were fine but cleaned them anyway.

I havent checked the common wheelarch earth stud that others had issues with but I'll get round to it.

I havent been able to achieve a consistent ride on my previous 2 l322s or this l405.

Battery terminals are clean, corrosion free and tight.

I like the idea about moisture in the air system but would that really have an effect?

Feels to me like the shocks just aren't soft enough but I know what it should feel like when normal thanks to Haylands allowing me to drive his so at least I know when mine isn't being normal.

IMHO water or moisture in the system will not effect it much...

A case in point...

Drowned in a Welsh river with water up to the bottom of the seats and then the suspension decides to level, on comes the pump with the intake under water, several ltrs pumped straight into the system...

Multiple cycles of pumping the water out and drying the dryer and no lasting effects... it made NO difference to the ride with water in the system....

It made me design and built a snorkel that worked...!! Pete
__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

For what it’s worth, I have also seen truck mounted equipment including air pressure switch and air solenoid valve damaged by moisture from truck/lorry air supplies.

But the amount of air in the system does not effect ride quality, it just determines ride height which is not the OP's issue... Pete
__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

The air pressure in the spring affects the spring rate, which very much affects the ride.

I agree. If you're feeling that suspension is harsh / stiff, its not going to be the air bags or pressure in them. If they were solid enough to affect the harshness, the car would look lifted up ... and it doesn't in this case.

That then leaves harshness in the mechanical arms and dampers. Take away the damper, and you're unlikely ( never say never ) to have anything seized to the point that the suspension would become stiff enough to affect handling. The reality is that a seized bush rubber would just get torn and the arm would move as it needed too as the car moved about ... you'd probably then be left knocking sounds from a worn out bush ... which doesn't seem to be the case here.

So with air bags ruled out, bushes likely ruled out, whats left that controls the movement of the suspension and its harshness is the dampers. Its already been shown in this thread that they can pop and go. I have had direct experience (albeit an evoque, but same tech ) of mine beginning to seize to the point ride quality was very harsh ... and this varied from ride to ride. Sometimes they bound up, sometimes not.

Initially it wasn't obvious to trace. The scan tools showed that the ride heights sensors were reading fine, and that the dampers were being sent a varying voltage/amp signal to control the damping rate. There were no errors from diagnosis... but there clearly was something wrong in the setup. I changed the diff, rebuilt the haldex, replaced rear suspension bushes ... all to no avail.

I found it by chance when jacking up the car ... I noticed that the wheel was being held up as the car lifted, then it would jerk down to the ground with a thud as the stiction from the binding damper released. On closer inspection of raising and lowering, I could see binding on the damper. Damper replaced ... all immediately fixed.

With hindsight, I reckon that when I was noticing the harshness, if I had pulled over, kept the car running ( so it remained in its current state ) and bounced on each corner, I would have possibly found that the car would'nt move smoothly like it should ... indicating a seizing damper.

Maybe you could try the same or similar ... drive about and if its harsh, stop, and push on each corner. If it doesn't move smoothly ... and moves like it hash stiction, it might give you a place to start looking. V8 or else ...

Good shout...  Pete
__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

That is a good shout Fisha and I do recall someone on the L322 thread I had saying he found a bad damper (as his bonnet was shaking up and down on one side of the car when driving) he replaced it and problem solved for him.

I put 4 new dampers on the last L322 to no effect though.

I have already bounced tested the L405 and all corners move but only a little probably as the shocks aren't energized into the 'soft' mode when the vehicle isn't moving.

Something else I'd like to look at is definitely the road force variation on the tyres... as we know from the road force balance I had done the n/s/r tyre measures 110 newton's of RFV which is only 10 newton's over the Hunter machines limit of 100 for an SUV.

That being said however I've found documentation from LR that wheel/tyre assemblies on the L405 shouldn't measure more than 60 newton's of RFV.

I've posted my road force balance results again below and I do have 2 tyres which are outside of LRs acceptable limits.

However these 2 tyres were on the car when I bought it. I'm just thinking along the lines of a person who once said that out of balance tyres can affect CVD operation.

Last edited by MarianaWestminster on 7th Sep 2023 8:24pm. Edited 1 time in total

i had a buckled wheel on the front off side of mine and it didnt affect the ride...this was found with a road force treatment..they put this wheel on the back for me and tbh i didnt find any difference..

as i mentioned in a previous post, playing about with my terrain knob has made my ride slightly better...placeable effect maybe, but this might have done something to the ride electronics... ... - .- -.




Y. O. L. O.
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Well that means that two wheel /tyres are quite a way over the limit set by LR, so that is one positive avenue to investigate.
One thing that came to mind is that if it is the tyres / wheels causing this 'rough' ride, this could also be affected by temperature, as the rubber flexibility will increase with temperature, possibly decreasing the effect as the tyres warm up through use, also tyre temp will vary, from lower in town to higher whilst on the motorway, thus affecting the car at different times.
Another point to maybe think about is to have the wheels checked for balance / distortion before the tyres are fitted. I have never witnessed wheels being balanced without tyres being fitted, but if the wheel was checked on the machine without the tyre first, just to start at a datum point from which to work forwards, this may help.
As for sticking damper possibility, you could try jacking the car up, put it on axle stands and then put a trolley jack under the tyre and lift to compress the suspension then let the trolley jack down quickly and see what happens, or simply lift the tyre against the damper with a long plank and block as a fulcrum, drop the wheel fast and see what happens. This may help to prove / disprove the damper aspect. Sorry, not much help but it's all I can think of after re-reading this thread.

Yes Merchy it does indeed.

I agree tyre temp definitely would have an effect because as well as rubber flexibility changing with the change in temperature the tyre pressure will also increase.

During the road force test all 4 wheels were checked for 'true' using the Hunter machine, it had an arm with some sort of dial indicator roller assembly which was ran against the inside rear edge of the alloy.

I watched whilst this was done and all 4 alloys passed, the technician informed me the high road force variation was down to the tyre and not the rim. An avenue to explore but at great potential unnecessary expense given both rear tyres have between 7-8mm of tread and are date stamped 2022.

Might get away with rotating the tyre on the offside rear to reduce the RFV. (Should have asked for this at the time but I did not know about the LR acceptable RFV figures at that point so was working to the machines accepted limit of 100 newtons.

I like that idea Merchy, will have to try it if I ever find the time... one busy man at the minute!

Last edited by MarianaWestminster on 5th Nov 2023 11:08pm. Edited 2 times in total

Any ideas what else I can look into here?

The amount of vibration and feedback felt throughout the car (body, steering wheel and seats... the passenger seat actually trembles) going down the motorway just isn't acceptable.

I know I've driven Haylands car and he's driven mine and says its fine but I just can't learn to live with it and accept it as normal.

The only thing I've got to go at is the rear tyres being over LRs acceptable road force variation limits but there are plenty of people who have new tyres fitted with normal balancing and have no issue.

Car was inspected at LR 2 months ago and they had nothing to report as far as suspension goes so I don't think it's bushes or balljoints.

Are these really, honestly suppost to be like this? Ie. Every single bit of the road surface is felt in the car?

I have just made a trip in mine and the only complaint is when the motorway concrete is a little rough or has break lines in it, it causes some rumble otherwise lovely and smooth and comfy. overfinch modified