Stiff Xantia Suspension

In news: snipped-for-privacy@posting.google.com, Chris Ward decided to enlighten our sheltered souls with a rant as follows

probably either a knackered front sphere (there's three each end on some of them, the third one determines "spring" and damping rates), or the self levelling control has seized. Not too expensive to fix.

Sphere or spheres knacked. Not a major job. They are a standard service replacement part on Citroens. About £20 each in France so expect to pay more here. Some suggest having them recharged with gas but for the little extra cost I'd buy new. If you subscribe to the Yahoo Xantia-L forum there are lots of knowledgeable folks who will help. Might help the old ones off if you give the threaded area of each sphere a good soak in release fluid such as Plus Gas a few days before doing the job. There are various versions with more or less number of spheres depending on the model. Also accumulator spheres so you need to know the exact type. Andyspares (GSF) probably the best place for parts. Just a reminder, never crawl under a Citreon unless it's blocked up on stands. DaveK.

Yup, learnt that one the hard way when doing an oil change! Can spheres fail so suddenly, because one night it was fine and the next morning it was verging on un-driveable!

Anyway thanks for the advice Chris

You can try "Plus Gas"ing the threads on Xantia spheres until the cows come home and it will do you little good (unless you're talking about the single rear anti-sink sphere where fitted), because on most of them the sealing O ring will keep the Plus Gas away from the threads.

-- James

If the ride height is "correct" at the front (i.e. not at the bottom or top of the suspension travel) it is almost certainly both front spheres (left and right) need replacing. If the ride height at the front is either too high or too low it is almost certainly the height corrector that is at fault. You can get a rough idea of whether the front is at the right height by looking at the gap between the ground and the sill, the ground clearance should be roughly the same at both jacking points.

Spheres don't commonly fail overnight, generally they lose gas and the suspension becomes gradually harder although it is not unheard of for a sphere to rupture its diaphragm. In your case if your suspension was happy and working correctly (i.e. both spheres were OK) yesterday it is unlikely that both spheres have ruptured overnight.

The height correctors do tend to stick occasionally (probably your best bet) but it's usually the rear ones that get sticky, the fronts don't get exposed to as much muck and spray when you are driving along the road.

-- James

Possibly. I found on my old BX that the change was gradual but then suddenly became noticeable on big bumps to the extent that it was possible to get one of the front wheels off the ground. Only one sphere had failed and it's probably unlikely that two would go simultaneously. If the ride height is wrong you'll feel every bump in the road.

-- Malc

Given the suddeness of the failure, I would have thought the plastic/nylon height corrector has gone. As it is a three quid replacement and a five minute job, might be worth checking before you do anything else.

Good luck,

SM