More on this. When the E70 3.0d first came out it was 173kW/520Nm in Euro spec but we only got a 160kW/500Nm version due to our diesel fuel quality (sulphur content basically). When the final stage of government's new standards for diesel fuel came into effect (Jan 1 2009 - sulphur content limited to 10ppm), we then got the full 173kW/520Nm version. All of which suggests that the tweak may be just engine management not mechanical.

Diesel fuel quality has always been a sticking point with Euro diesels in Australia. Before the first sulphur standard came in (500ppm in 2003), BMW said that they would not import diesels to Australia. When that first standard came in that's when they launched the first-generation 135kW/390Nm diesel in the E53.