The diesel is a straight 6 and if built from late 2004MY onwards will be a 218bhp/500nm torque unit with a 6sp ZF transmission for auto, or a 6sp manual option (186bhp 5sp models before that). Much more economical than the petrol models - I regularly see 35mpg plus on a motorway, 27mpg around town - petrols will be rather less with the V8's likely to be in the low twenties to high teens!! In the UK, most 'X's are diesel - but not badged as owners tend to remove the engine badges.

Diesel engines should last longer than petrols as they are less stressed (lower revving) units. The auto transmission is a known weak point, but not in every case. Plenty of owners have never had a problem. The manual may well eat clutch plates if you tow or do a lot of town driving. Very few manuals in the UK as no one wants them second hand, and in my case the dealer wanted a massive deposit if I stuck with my original choice of a manual (one reason I changed to the auto). Turbos are worth checking too as a poor oil mantenance by an owner can cause the premature failure of those too - rare though.

Whatever you go for, make sure it has a full service history and check EVERYTHING (all the switches, mechanicals, electrics etc) very carefully before handing over any money

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