New to X platform

[///ASN]

Hi everyone,
Coming from E92 platform, want to get a X6, deciding between 30D & 40D and hopefully to get some advices here since X5/X6 probably uses the same chassis:

1) are there any common issues with the 30D or 40D engine?
E.g with the 335 that I have got, prior to 2009 model is having common problem with the water pump, thermostat & HPFP. Revised parts are introduced at certain production year

2) 40D: earlier model equipped with DOHC with VVT, the later model with overhead cam better, which one may be more reliable in terms of longevity?

3) apart from the engine, what are the difference between 30D & 40D? e.g. Standard lower suspension, rims etc

4) in general, any recommendation as to which mode to get or what to look out?

Thanks.

[Entr0py]

Why don't you actually read these forums !!!

The questions you are asking are all answered on the first 3 pages -

How Lazy can one be !!

Just kiddin' .... good luck with that rattle trap diesel