im going to have to throw a nomination up for the ra rodeos 3.5 isuzu v6, they burn oil like you cant believe, chew petrol and sound like its going to explode when revved, i all ready know of one thats done a bottom end and a head, and its done just over 100,000km, so no warranty on that one,
i believe the 3.2 version in the previous models is similar,
the best thing holden did was sticking the alloytecs in them, although the clutches are a little odd