The TD4, TD5 and TD6 were a series of engines that BMW introduced when they were in control. I read an interesting article about these at Zooks place in i think Land Rover Monthly. These engines are practically identical appart from the 500ml increase in size with every cylinder added from the TD4 2.0L to the 3.0L TD6 in the rangie. These engines were a master plan of BMW and were supposed to be a long term engine to last long into the future, they were designed to meet emission standards long into the future with slight mods over time, the excuse ford used may have been true about not meeting emmission regs but with the mods BMW planned they would have, they just wanted their own 'in house' engines in the vehicle. Matt