service.citroen shows different part numbers for the turbos on XMs and Xantias...the arrangement of connections air side looks different, and the orientation is different. That's not to say however, that it's not the same basic turbo with different inlet / outlet housings bolted on, and you couldn't relatively easily build a good one that will fit out of the two. Worth a punt given the likely cost of a replacement (XM ones are NFP, Xantia exchange is £1002.71

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A new one is not that much more dear, a snip at £1234.84
