C5 Metallic Clonking From Rear,suspension?

[delart]

Hi got a 110 HP HDI that has developed a metallic clunking from rear o/s between the radius arm and sphere, the hydraulic ram? It is an exclusive 2003 what type of hydraulic fluid should be used for this type of suspension?

[paul.h]

Welcome to the forum.

 

The C5 uses Total LDS fluid for the suspension. http://www.gsfcarparts.com/980aa0720

 

 

I have moved your post into a subforum since ones outside do not show after a few days and are then hard to find.

[delart]

Thanks that looks a different colour to what I can see in the reseviour? Looks green how much do they take?

[Johndouglas]

The LDS used on a C5 is orange/yellow in colour.   If your fluid is green, it's very likely that someone has used green LHM - the suspension fluid that was used on all hydropnuematic Citroen BXs and Xantias..   Will LHM damage a C5?   Some guys say No;  others say Yes - but since Citroen have introduced  a new fluid for C5s and 6s, and the container carries a warning about mixing the two, my advice would be to get it changed. 

[paul.h]

According to the Haynes manual the LDS fluid capacity is 

- the hydractive 3 system - right hand drive 4.7 litres, left hand drive 4.5 litres

- the hydractive 3+ system 5.4 litres.

 

On top of this you would need more to flush out all the incorrect fluid - this might involve draining the old fluid, filling with new, using the suspension, draining again and then refilling and possibly repeating this. Haynes states that using the wrong fluid will damage the system rubber seals and hoses so some of these may need replacing. Check the front and rear struts and all the piping/hoses/steering rack/suspension pump/power steering pump/spheres for any signs of leaks - if any are found the replacement cost can be high - a new rear strut is about £150, a new front strut is about £350.

[delart]

Thanks for help people, can you drain the system completely or is a case of some in and some out?

[paul.h]

You can probably get most of it out by removing the tank bottom hose, putting the car on a ramp so it is raised and supported on the wheels (with enough ground clearance so you are not squashed when the car drops) and then opening the front and rear bleed/drain screws. The car suspension will then drop as low as it will go and push out the fluid. If you measure the amount removed it should give a good indication if most of it is drained.

 

I have read elsewhere on the internet that the LHM fluid may not damage the C5 system and if a bit is left in it probably would not matter so it may be worthwhile you doing a bit more research.

 

The Haynes manual is useful if you do not have a copy. When you refill the system if the suspension pump does not prime I have read on here that you can simply blow in to the tank to push the fluid to the pump and also just leaving the car overnight may be enough.

[paul.h]

What are you thinking of doing about the metallic clunking, do you know what is causing it ? If it needs part of the suspension replacing and the fluid needs draining, it may be best to sort this first or at the same time as replacing the fluid. If you do not know the cause, one possibility is the brake caliper may be catching the wheel due to corrosion between the caliper and suspension arm. See the pinned post on removing the rear brake caliper.

[JoshC5-138]

When you go down a bumpy road try dragging the brakes very slighty I've just had this problem it was the rear pads rattling in the caliper :)

[paul.h]

In the parts diagrams Citroen now include extra shims to go over the top of the rear pads, clipping to the spring. These stop the rattling/clonking as the brakes are first applied. This is noted in the Common Problems pinned post in the C5 Technical section as follows:

 

3. Rear brake pads clunk when the brakes are applied.

If the brakes are kept well serviced, they may be heard to clunk when going slowly. Citroen supply an extra shim to attach over the pads on the retaining springs (part no. 442701) and this worked on the hatchback. Shims £14, new springs £2 (in 2011).

[delart]

Well I only ordered two litres of LDS and rightly or wrongly drained two or so litres off and replaced with LDS and it defiantly ride's better need to order some more and billed off and replace. Not conclusive!

[delart]

Hi thanks for help so far, it looks to me that it is lower on the rear o/s and there appears to be "play" between the radius arm and hydraulic ram?? Anybody had this problem ?

[paul.h]

Best way to check the height is by measuring the height of the wheelarch above the centre of a wheel. Is the R pin in place holding the ram piston rod to the radius arm ?

[delart]

Yes the r clip is holding it but it is loose, it is like it needs more pressure? Really could do with a drawing. Do they do replacement parts or is it a citroen complete strut.

[paul.h]

The R clips can rust in over time but if it is loose maybe it has rusted a bit thin or there is an oil weep from the strut on to it keeping it clean. With it loose, pull it out and check its condition and if bad then replace it with a new one (about £2 from Citroen). A bit of grease where the strut rod goes in to the cup may help with the noise, if that is the source of it, but the rod should be held in tight in the cup by the weight of the car on the suspension.

 

You can see the parts diagrams as a free service on the service.citroen site if you register as an other professional, member of the Citroen Owners Club.

[delart]

Hi thanks again for help. Can anybody recommend a citroen specialist around mid wales. Seems to me I need a new strut but even if I go to main agents it is a part they have to order in, so it would be a two day job and the closest is a 100 mile round trip.

[delart]

Hi I bought a second hand hydraulic ram but it was the wrong type as it had a large feed to it and mine has a small bore feed like a brake pipe. Anybody know how many types there are.

[paul.h]

There are 4 different rear struts for each side. The right one depends on if the car is an estate or hatchback and also the RPO number. To get the correct one you need to use the car VIN in the parts diagrams. 

[delart]

Thanks nothing is simple, are the different type's two for hatch and two for estate, Vtr and exclusive? Need to try and sort this as I want to get an estate but while have this going on not sure which to get. LPP RPO number?

[paul.h]

There is 1 type for the estate and 4 for the hatchback which includes the estate one. To get the right one you need to use the car vin in the parts diagrams.

[delart]

Hi just an update, I decided to bleed the ram on the side that was clunking and have done about a hudred miles and noise has virtually disapeared and car a lot smoother now. Will bleed some more of soon. What is the bleed nipple in the centre for? Or have I answered my self.

[paul.h]

The bleed nipples in the centre at the front and at the rear are to drain the lds fluid out. Using the front one will drain the front and using the rear one will drain the rear. If the car is not on axle stands, the weight on the suspension will push the fluid out as the struts are compressed but at the same time the car will drop on to the rubber bump stops leaving just a few inches ground clearance.

[delart]

Hi I have measured up and the o/s/r is defiantly lower than the n/s/r, what if anything can be done?

[paul.h]

It may be worthwhile checking the bushes/bearings in the suspension arm in case at one end it is faulty. Also have a look at the wheels from the rear and see if they are leaning in at the top - also a sign of the bearings being faulty.