D4 Suspension Problem

[rhinosm]

Hi
i have an issue of front passenger side being lower than driver side, around 15mm on average.
It can be more in the morning.
After driving it comes up to within 10-15mm difference.
To me the front looks like it’s sitting low.
If it was losing air, wouldn’t the whole car drop?

One suggestion has been a height sensor.
I did damage one a few years ago and was replaced, massive pot hole.
I’m wondering if another is faulty also.

Following the car on the freeway it looks like it is leaning down to front corner.

Any thoughts would be greatly appreciated.

cheers

Vin

[Graeme]

Leave overnight with the 20A suspension system fuse removed. This will prevent periodic levelling which will then allow a leaking corner to lower by itself. Leaking can be from an air-spring or the corner valve in the valve block.

[rhinosm]

Thanks Greame
So you think a sensor, more likely air leak.
Looking at it today and comparing to other D4s I see around, the whole front is sitting low.
Very frustrating.
I think it’s been that way for a while, now that I think about it.
Vin

[Graeme]

An air leak is easy to confirm or rule out and needs to be ruled-out before considering sensor calibration.

[rhinosm]

Hi
Last night I measured both sides of car, 4mm difference for the record.
Pulled the fuse.

This morning the car had not dropped at all, mm perfect.

I monitor as I drive it today.

The front still seems too low compared to back.
I will compare against friends D4 today.

Thanks

[DiscoJeffster]

Hi
Last night I measured both sides of car, 4mm difference for the record.
Pulled the fuse.

This morning the car had not dropped at all, mm perfect.

I monitor as I drive it today.

The front still seems too low compared to back.
I will compare against friends D4 today.

Thanks

Take measurements from the wheel arch to the hub centre. Front should be 466mm, rear 485mm. That will tell you if it’s sitting low.

[Eric SDV6SE]

Re calibrate the height sensors now that you've established there's no leak.

[rhinosm]

Thanks
whats involved in Re calibrating sensors?
vin

[DiscoDB]

Take measurements from the wheel arch to the hub centre. Front should be 466mm, rear 485mm. That will tell you if it’s sitting low.

And unless you are in Tight Tolerance Mode, individual heights can vary by up to 10mm. So it is possible to see a 20mm difference across the front or rear.

[rhinosm]

So heights front-end rear look good on driver side, 465 & 485
Passenger side 10mm both front and back.
Would that be considered normal?
Vin

[DiscoJeffster]

So heights front-end rear look good on driver side, 465 & 485
Passenger side 10mm both front and back.
Would that be considered normal?
Vin

I had that and it was consistent and noticeable. Did you measure it on a completely level surface? As mentioned, there is a level of tolerance in the system but I’d say if over a number of days, if you’re getting consistent reading and there’s always a bias to the passengers side, it warrants a recalibration.

[rhinosm]

Thanks
Yes always a bias to passenger side.
Is recalibration something a service centre needs to do?

[BradC]

You have got the same sized tyres on each corner haven't you? [wink11]

[DiscoJeffster]

Thanks
Yes always a bias to passenger side.
Is recalibration something a service centre needs to do?

You can do it with a tool such as the GAP IIDTOOL. That’s how I did mine. Mine was lopsided when I bought it.

[rhinosm]

Update
Calibration not successful.

Report from LR Dealer inspection,
Upper control arms after market causing height sensor to not sit right affecting height calibration. Will require genuine arms.

[loanrangie]

Update
Calibration not successful.

Report from LR Dealer inspection,
Upper control arms after market causing height sensor to not sit right affecting height calibration. Will require genuine arms.


disconnect the sensor and bend the bracket in the desired direction, do you know what arms are fitted ?

[Eric SDV6SE]

Update
Calibration not successful.

Report from LR Dealer inspection,
Upper control arms after market causing height sensor to not sit right affecting height calibration. Will require genuine arms.


What a load of BS. I've fitted aftermarket arms on mine, brackets are in the same position, fabrication is marginally better than genuine (less weld spatter and proper chamfered edges).

Go to an Indie familiar with these, should be a 10minute job.

[DiscoJeffster]

What a load of BS. I've fitted aftermarket arms on mine, brackets are in the same position, fabrication is marginally better than genuine (less weld spatter and proper chamfered edges).

Go to an Indie familiar with these, should be a 10minute job.

Welllllll, we don’t know what arms HE has so while I agree it’s unlikely, it’s still possible. You’d have to think the wrong arms were used if that’s the case.

I do agree though it sounds like a stealer angling for a big $$$$ repair [emoji2369]

[imaz]

You have got the same sized tyres on each corner haven't you? [wink11]

Sorry to hijack this thread, as I’m looking for answers or a leak.

How much of a margin difference sized tyres make at each corner effects the suspension levelling?

I’ve got 1 Chinese made temporary tyre on one corner, rear right and although it is the same size 265/50/20’s, it’s measurement to the rest of the tyres is smaller by maybe 2cm or an inch overall height... strangely, my vehicle when parked overnight is lopped at this corner...


Suspension measurement test - Normal ride height.

Removed F3(5A) fuse

@6:05pm
R/R 485mm
F/R 465mm
R/L485mm
F/L 465mm



@10:50pm
R/R 370mm
F/R 445mm
R/L 440mm
F/L 490mm

When the vehicle is started, it levels out.

[loanrangie]

Sorry to hijack this thread, as I’m looking for answers or a leak.

How much of a margin difference sized tyres make at each corner effects the suspension levelling?

I’ve got 1 Chinese made temporary tyre on one corner, rear right and although it is the same size 265/50/20’s, it’s measurement to the rest of the tyres is smaller by maybe 2cm or an inch overall height... strangely, my vehicle when parked overnight is lopped at this corner...


Suspension measurement test - Normal ride height.

Removed F3(5A) fuse

@6:05pm
R/R 485mm
F/R 465mm
R/L485mm
F/L 465mm



@10:50pm
R/R 370mm
F/R 445mm
R/L 440mm
F/L 490mm

When the vehicle is started, it levels out.2cm is a big difference and not so much affecting suspension height but would play havoc with the speed sensors and abs/DSC. I would be changing that asap.

[imaz]

So what are you all replacing the airbags with? Are you going genuine or aftermarket replacement? Replace the failed or in pairs.

Huge price differences for aftermarket vs genuine.

[BradC]

Huge price differences for aftermarket vs genuine.

When working on, in or around the Discovery I always ask myself "is this a job I want to do twice?". The answer generally covers the cost difference.

[imaz]

When working on, in or around the Discovery I always ask myself "is this a job I want to do twice?". The answer generally covers the cost difference.

I take it doing the job twice is genuine part where quality is not considered [emoji1787]

[Eric SDV6SE]

After lots of research i generally choose OEM- it's the same item but just not in a LR box.

Depends on the item too. Re your question, I bought the Delphi units from Advanced Factors

[ramblingboy42]

quote...2cm is a big difference and not so much affecting suspension height but would play havoc with the speed sensors and abs/DSC

this quite concerns me , that having a different , though supposedly same size tyre fitted , can totally change the driving dynamics of the vehicle.

it concerns me to the point where my plans of re-entering the Land Rover fold may be completely shelved

there are many more options available in the motoring market without that sort of headache......I go bush a fair bit and see no joy in that happening if I have to put a different tyre on.

[loanrangie]

quote...2cm is a big difference and not so much affecting suspension height but would play havoc with the speed sensors and abs/DSC

this quite concerns me , that having a different , though supposedly same size tyre fitted , can totally change the driving dynamics of the vehicle.

it concerns me to the point where my plans of re-entering the Land Rover fold may be completely shelved

there are many more options available in the motoring market without that sort of headache......I go bush a fair bit and see no joy in that happening if I have to put a different tyre on.On no vehicle is it acceptable to have a tyre that is 20mm different to the rest,it defies logic.

[Eric SDV6SE]

Replace the failed or in pairs.

After 200 000km on the original struts and airbags, I replaced all four with Delphi / BWI units. Ordered the two fronts and 2 rears under separate orders, keeping the value below 1k each order.

[DiscoDB]

So what are you all replacing the airbags with? Are you going genuine or aftermarket replacement? Replace the failed or in pairs.

Huge price differences for aftermarket vs genuine.

Always do in pairs, unless in an emergency situation.

And in the case of struts, OEM from a trusted supplier like Advanced Factors or LRDirect is what you want. In this case it is BWI/Delphi.

[BradC]

it concerns me to the point where my plans of re-entering the Land Rover fold may be completely shelved

Let's take a worked example.

A 265/50/20 has a diameter of 773mm (275/45-R20 vs 265/50-R20 Tire Comparison - Tire Size Calculator | Tacoma World (https://www.tacomaworld.com/tirecalc'tires=275-45r20-265-50r20)). That's a circumference of 2.427M. The tyre in question being some ~2cm shorter (753mm) has a circumference of 2.365M. The main 3 tyres on the vehicle are 4.3% larger. That's 443 Rotations/km vs 412 Rotations/km.

Let's take a limited slip diff for example, you are rotating those clutch plates 30 times per kilometer, or once every 33.3M. At 100kph that's just under once a second. That's enough to cook the fluid in a Haldex (as found on most AWD passenger vehicles from the late 80s til current). Even if the clutch isn't engaged, the shear force on the oil is enough to generate enough heat to cook it. Now think about what that does to the clutches in the transfer case of a D3/4.

Any vehicle more complicated than my 2WD 1988 Volvo with an open diff is going to sustain damage if you persistently drive like that. Nothing to do with the D4 being fragile and complex, but everything to do with doing something really dumb.

[imaz]

I remeasured it, it worked out around 1.5cm difference - but I get it, the tyres getting changed. Spare was used as I ripped the original tyres on a trip and has been pending for a change. But I will also be placing an order for the BWI’s(pairs), may also do the fronts also.

[ramblingboy42]

sometimes in the middle of Australia with thousands of km left to travel on your journey it is not possible to fit and match an OEM specified tyre or in the case of a lot of members here non OEM sizes. how many of you can get the tyre you want in the bush?

twice now I havent been able to in Roxby Downs. neither can you get much choice in the nearby town centres....not even in the Flinders ranges.

you have to take what choices are there for you.

to call someone in this forum dumb for driving on a non matched tyre out of necessity because the vehicles electronic counter measures can put it in an out of control situation is not really fair on the member who posted looking for help.

[imaz]

sometimes in the middle of Australia with thousands of km left to travel on your journey it is not possible to fit and match an OEM specified tyre or in the case of a lot of members here non OEM sizes. how many of you can get the tyre you want in the bush?

twice now I havent been able to in Roxby Downs. neither can you get much choice in the nearby town centres....not even in the Flinders ranges.

you have to take what choices are there for you.

to call someone in this forum dumb for driving on a non matched tyre out of necessity because the vehicles electronic counter measures can put it in an out of control situation is not really fair on the member who posted looking for help.

I don’t know about you, the only guy in the middle of Gibb had 1x Chinese 20” tyre in his bush tyre shop. He claimed you won’t find any 20” in the Kimberly region without ordering them. Never the less, I did bring spares but of not matching pattern in hope I don’t need to use them. Who would have thought the rolling circumference can make significant difference if the sizing is the same.. to chew through 2 new At3w tyres in 3 weeks was gold!

[BradC]

to call someone in this forum dumb for driving on a non matched tyre out of necessity because the vehicles electronic counter measures can put it in an out of control situation is not really fair on the member who posted looking for help.

Oddly enough I was responding to your comment which says "this quite concerns me , that having a different , though supposedly same size tyre fitted , can totally change the driving dynamics of the vehicle.

it concerns me to the point where my plans of re-entering the Land Rover fold may be completely shelved"

I was simply pointing out that regardless of your further comment regarding "vehicles electronic counter measures" driving with deliberately mismatched tyres is a (potentially severe and damaging) mechanical issue regardless of the electronics and I tried to explain *why*.

Sometimes in an emergency we need to do what we need to do, but generally you do it extremely carefully and only for as long as is absolutely necessary. Perhaps the characterization of "dumb" was un-called for, and I apologise for using that specific term.

[loanrangie]

And that's why you would choose a size and brand that is more common if you are going remote, I wouldn't be running 20" rubber bands anywhere far from a large town, plenty of options to drop down to 18" rims and tires.