fitted monroe comfort spheres...

[EDC5]

I was rather disappointed with my C5 (Mk1) compared with the XMs although the hydractive was better but the 2.2 engine dreadful on fuel.

Peter

How bad are we talking economy wise. My C5 is the 2.0 138 auto and gets around 47-49 mpg at 70 and about 35-40 around town.

[Peter.N.]

My 2.0. 8 valve did around 50-60 mpg the 2.2 was in the 40s with a best of 50 driving very gently on the motorway. I suspect that there may have meen something wrong with it though because I drove my sons 2.2 Coupe back from Telford and got over 60mpg.

The suspension on my 2.0. C5 was very choppy even after I had fitted new spheres and trailing arm bearings, to be more precise it pitched from side to side on uneven road surfaces. I drove someones XM estate after I got rid of it and the ride was superb.

Peter

[white exec]

In Soft mode from Hydractive, it's the centre spheres that provide the soft ride, and they have no damping - damping is built into the front and rear centre sphere Electrovalves, where lateral roll is also hydraulically damped. Since the centre spheres contain no damping (just a big hole, as Peter says), there is no advantage to fitting "comfort" spheres here.

Non-standard Comfort spheres have various larger sizes of damper orifice, and are often higher gas pressure too. This latter will give extra resilience ('more springing' / greater movement), but there is a limit to how much vertical movement the mechanical suspension components will allow.

If the centre spheres are correct size and gas pressure, the ride on Hydractive is usually very good. If gas pressure is low, comfort will be compromised.

Firm ride occurs during normal driving whenever steering, brakes or throttle pedal are used with enthusiasm. The system also flips quickly to Firm if/when the car encounters a sudden or sizable change in road surface height (eg hump or ridge), when the body movement sensor (attached to the front roll bar) kicks in.

It's this latter (Firm) suspension behaviour that attracts criticism, because it can come across as harshness, and can contrast starkly with a soft and floaty ride from the suspension when operating Soft.

To prevent the Firm mode from being crashy or hard:
- avoid tyre over-inflation, even by a couple of psi.
- make sure corner spheres are the correct type, size and gas pressure
- make sure there is no air in the hydraulic system (check for bubbles, even microscopic ones, at the reservoir)
- bleed the hydraulic system (at the brake calipers; rear calipers bleed air from the rear suspension too)
- check that the front and rear Electrovalves are working (bounce test)
- flush system with Hydraurincage, renew/clean reservoir filters, renew fluid, if car has done years of service
- do a session of Citrobics every so often - keeps system supple and helps expel trapped air

If you are going to fit Comfort spheres (and there is disagreement about the wisdom of doing this), then they should be used for corner (wheel) spheres, not the centre ones.

Everything above relates to Hydractive I and II.

[myglaren]

Chris - it's a C5 so bleeding the system at the calipers won't work, braking and suspension are completely separate systems, also Hydrorinçage is inappropriate for the LDS system.

I agree with the Citroebics though, do it frequently with mine, more to lubricate the otherwise unused portions of the rams, exercise the trailing arm bearings - same reason, and to run the motor to help keep any condensation/moisture out of it.

I have found that loading it up with heavy weights seems beneficial too, with the concomitant reduction of performance and economy.
Overloaded my estate with heaps of MDF and it rode much nicer for the three days following

[white exec]

Yes, apologies for the C5 errors.

[Smarty2]

Sooo, is there a difference then between IFHS and Monroe comfort spheres or doesn't anyone know?

[white exec]

. . . also Hydraurinçage is inappropriate for the LDS system.

You got me wondering what the recommended flushing agent was for LDS systems . . .

Source: Citroen, Private Cars C5-C8 2005, CAR000.020 Vol.3 p.29

Or was something else specified later?

[myglaren]

As far as I am aware there is no procedure defined for flushing the LDS system.
The only thing I have heard is that inspection is recommended at the five year mark but no action specified.
As the fluid is not circulated as in the previous systems it is likely that contaminants don't accrue and need to be flushed out.

[GiveMeABreak]

That's correct Steve - no procedures listed in the service docs for flushing on the X7 with LDS and to be honest, no mention of flushing mentioned in the service docs for an LHM Xantia II and if it wasn't for checking the recommended lubricants docs, Hydraurincage isn't mentioned anywhere else that I can see.

[EDC5]

I've been tempted to bleed the rear suspension of my C5 and then replace the LDS with fresh at the front. Not for any particular reason but the thought of the LDS moving back and forth by about an inch doesn't give much opportunity for oil replacement through normal use.

[lexi]

You can drop the fluid straight out of the tank in older C5. Fill up again, then flush out remainder at rear valve. Not done it yet but fluid here and is on the cards. It is meant to make a difference. Your 2.2 will have Hydractive 111 plus?

[GiveMeABreak]

I've been tempted to bleed the rear suspension of my C5 and then replace the LDS with fresh at the front. Not for any particular reason but the thought of the LDS moving back and forth by about an inch doesn't give much opportunity for oil replacement through normal use.

Yes X7s are Hydractive 3+, but Elis has a a 2.0 Lt.
If not using Diagbox, manual method is:
Disconnect the battery.
Raise the vehicle and support on axle stands, wheels free.
Put a hose on the pressure release screw (2)
Gradually unscrew the pressure release screw
Wait for the pressure in the circuit to fall fully

[darbuck]

Just wondering lads mine is a mark1 C5 estate hydractive not hydractive 3+ so no centre spheres has anyone changed the spheres for comfort spheres and found them to make much of a difference. She is comfortable and smooth at the best of times but sometimes especially if I am driving long journeys she can stiffen up and feel like there is no damping at all. I am putting this down to bad spheres but I don't know.

[GiveMeABreak]

Not on a C5 to be honest and definitely not on the C5 X7 with hydractive 3+ (IFHS actually exclude the X7 from their comfort range). I think once you've accepted you won't get the 'DS' ride on the later models, it doesn't bother me. The car has good days and bad days - rides like a dream and other times as bumpy as hell - I just put it down to the bumpy twisted pot holed roads where I live.

[darbuck]

OK Marc thanks for that I was playing with the idea for a while and I just kind of wanted to confirm its not in my head as well that the suspension can be erratic she's still more comfortable than A Saab 9_5 I owned briefly over the summer seriously disappointing car uncomfortable and terrible handling I live in Ireland's pothole central In the middle of the bog so roads collapse regularly hence the need for a well damped motor.