I have been towing a Lunar Delta 610 with an GVW of 1600 kgs with a 98 300 tdi auto, and have been up Telegraph Hill numerous times, and the temperature did not move. It returns 25 mpg when towing and pulls very well. The vehicle has done a genuine 120K miles, the EGR has been removed and the intercooler flushed. It has been awesome in every respect and I have now bought a TD5 auto which will be taking over towing duties and the 300 tdi sold, that is when I am confident the TD5 is as good if not better than its predecessor.