Which used BMW X6 4x4 should I buy?
The entry-level diesel is the 30d. It has six cylinders and feels suitably muscular at low revs, yet is no slouch when pushed hard. As the best blend of price, performance and running costs, it’s the one we’d pick.
However, there are two further diesels should you want even more performance. First is the 40d, which is based on the same engine as the 30d but adds more power and torque. That means a quicker sprint time, but also worse official fuel economy.