I have a 2001 P38 2.5D automatic and tow a 1500kg caravan but find it a bit wanton on power as it seems to want to drop a gear everytime I accelerate. If I use the cruise control an set it at say 55mph when towing and I hit an incline it keeps going up and down the gearbox and the engine seems to be struggling away. Can anyone suggest anything that can be done to increase the power to stop this happening bearing in mind that I am getting about 16-19mpg towing and would not like that to drop or it would make towing my caravan a no go.
Thanks
Rob

 

The laws of physics are hard to ignore. Small engine, big trailer. Read through this for some ideas and constraints. 2.5 diesel performance vs BMW figures