Advice on buying E70: which year, model?

[the_ulf]

not sure the E70s even came with the M54 engine. i always thought they were all N52s and then N55s. every engine is a compromise. the N52s have the lowest number of things that go wrong on the engine itself, as far as i know. i'm quite fond of my N62, although a lot of people had some bad experiences. the diesels suffer from a lot of emissions related issues. the turbo 6s and 8s have their own set of problems and absoluetly all of them will see issues with each and every oil seal around the engine, from the valve cover gasket/s all the way down to the oil pan gasket. be prepared for having to change a lot of them. also, the earlier ones saw a lot of transmission related issues. it all depends on how adept you are with your hands and whether or not you've easy access to a hoist. literally the worst part about them is the lack of space around the engine. almost every job can quickly turn into a major arse ache.