My XM has now done 143000 miles (It's a MK 1 crossplatform petrol turbo auto) and it's not as smooth as it once was. There is a roughness or sort of vibration that you can feel at your feet as it seems to come via the footwell. Both driveshafts and the intermediate bearing have been replaced in an effort to overcome this problem but it is still there. The obvious things like wheel balancing have been tried several times too,still it persists.
Now I'm begining to think could it be engine mounts? I know the car has done a fair mileage and the main and big end bearings are not going to be quite as tight as they once were but is it expecting too much of the old girl to be as smooth as she used to be? I had a complete stainless exhaust system fitted last year and that has all been checked several times as a possible cause for transmitting vibrations from the underside, but all the mounts look fine and the clearances are there between system and floorpan.
This roughness is particularly noticeable when on the overun going downhill in 2nd gear using engine breaking it becomes very apparent then.
Any thoughts or suggestions would be appreciated!
Regards Merv.

Hi XMerv

A very rigid exhaust can effectively add an extra structrual member. It might be worth trying different (larger, more rubber) exhaust mounts. The 2.5 TD has a 350mm long braided flexible section designed into the exhaust down pipe behind the engine. This suggests that engine vibration transmission to the body shell must be borderline on other XM's and rely on spec items correctly set up for control. The stainless steel exhaust cannot be to full Citroen design spec as it is much more rigid than a standard exhaust.

John