Citroen ZX: Replacing rear subframe mounts

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Citroen ZX: Replacing rear subframe mounts

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Posted By Dave Burns with additions from JW
Car has to be supported with stands at the rear jack point's on the sill's, use a piece of thick plywood between stand and sill.
Remove spare wheel cage, pull rubber silencer mountings off (washing up liquid helps them slide off) and rest silencer on something suitable, there isn't enough movement available to lower it to the ground IIRC.
Unclip handbrake cables from fuel tank, wire brush and WD40 the protruding threads on the axle to mounting bolts and loosen them.
When I do these mountings I also remove the lower bolt's from the damper, this lets the trailing arm's swing down releasing any spring tension on them, if you don't the residual tension on the springs can twist the axle making withdrawl of the axle mounting bolt's awkward, and re-alignment even more so.
When the axle mounting bolt's are loose and turn freely, get a trolley jack under the centre of the axle tube, remove the front mounting nut's inside the car (you only have to pull the rear seat forward, don't take it out), then remove/lift boot carpet to undo the nuts for the (square) rearmost mounts. Once all nuts are undone lower the jack allowing the axle to swing down, watching the flexible brake pipe while doing so.
Swap the mounting's, bung plenty of copper grease on the bolts, and carefully jack it back up, make sure all bolt's are tightened securely.
The only real difficulty you might encounter is the external mounting bolt's, the protruding thread will be heavily corroded, I use a thread restoring file in such cases, this cleans out the rust from the valleys in the threads making removal of the nut easey, the bolts them selves can also be rusted into the axle mounting holes, plenty of penetrating oil usualy gets them going though.
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Post by Guest »

Finally got round to doing my ZX rear mounts yesterday at 121,000 miles.
See the "Common Problems and Fixes" section for more details on this, and in particular the wise words of Dave Burns.
I was very lucky that I was able to do this job on a 2 post ramp and used a hydraulic gearbox stand to support/lower/raise the rear beam, together with a step ladder to get up into the car to undo the mountings with out raising and lowering the ramp!! Thanks as ever to Louis Barbour for this.
Anyway, using the time served motor trade technique of the 1/2" drive windy gun with the 18mm socket and the spanner on the other side I quickly removed the front mounts. Fitted 4 new mounts. Put the 2 nuts and bolts back in on the o/s/f mount, and did it up. But, the nuts just span uselessly and did not grip the mount. Doh. At this point I remembered Dave's wise words about using a thread file after the nut and bolts are removed!!! Out with the angle grinder then to take them out.
By a miracle Louis had the correct (M12??) nuts and bolts in stock! When I came to do the L/H side I carefully cleaned up the threads, and used new lock nuts, all was well.
Couple of other things, When removing the rear dampers don't do what I did and remove the top damper mounting. Although it makes it really easy to change the front mounts its a nightmare to refit the damper. Far better to undo the bottom damper nut, then gently tap through the stud (be careful of the brake pipe!!). Makes it loads easier to refit the damper.
Also a good idea to have at least one brake flexi hose on hand, on the r/h side I gently moved the hose using only hand pressure to get a spanner on the subframe mount, and brake fluid started gently seeping from the top of the hose. Had to fit a new one.
In conclusion, use a thread file as Dave suggests on the front mount bolts, and I would stongly advise new lock nuts as well. Saves a load of hassle.
On the bright side, it was all done by Saturday lunch, it only cost me the 4 mounts, the clonking has gone and the ZX handles like it used to. Roadtest to a wedding in Thurrock on Saturday night then back to home, 175 miles and just great.


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