Citroen XM Forum

Great i think I'll replace with a steel oil cooler, now to find a suitable one on eBay...

Should be easy to find. Go for one with decent depth (height), rather than one of the very thin ones for small engines. I think these were made in at least a couple of depths. Centre tubular 'bolt' will be needed to match; thread is M20 for both the engine flange and the normal filter.
A serviceable rectangular-section filter O-ring will also serve for the underside of the cooler, as diameter is the same.
Water connections may need jiggling if not in the desired orientation.

Hoses usually need extending with bends to fit.
While I agree that cleaning out after a failure requires quite a bit of work I still let the originals run on.
I think Chris has been very unlucky to experience two failures on his single car.
The problem as far as I can see is from variable quality of manufacture rather than severe in service degradation.
So I pressure test before reusing recovered ones.

John