daul cab fuel useage

Presuming the engine systems are sound.

Since it is 2008 it may require the MAF and MAP sensors to be cleaned with sensor cleaner. CRC make one for the task. MAF is just after the airbox and the MAP, (the one which gets gummed up and filthy) is before the Throttle Body housing above the intake manifold. The MAP senses the intake boost pressure and if claggy it may not indicate true boost to the ECU and the system will be out of whack.
Both are held in with two or three screws and has a wiring connector to each.
If they aren't clean it won't return good economy, normal about 9 to 9.5L/H empty.

Air filter clean?
Bigger tyres? or wider?
Is it auto?
Already weighed down with extras?
Air drag of roof rack?

The faster you try and move more weight the fuel use increases in a logarithmic fashion.
ie, Not much distance for a lot of fuel.

Yer thanks Ross , got a roof top tent etc & only 235 coopers on & is manual ! I will have a go at cleaning those suggested before return trip , many thanks

That fuel usage look about spot on for the trim in its in, especially with the different ways it gets driven. Weight, wind resistance and a bit of right boot really makes quite a difference. I recently unloaded what I thought was minimal gear (200 odd k.g.) from a Colorado we were trading in and in the couple of weeks I drove it empty the usage dropped from 13/14 to 10/11 per hundred around town.

Sounds about right similar to what my neighbour gets, the drag from the tent would be biggest downfall a wind deflector might help you would have to experiment with angles. Other than that a snorkel can help economy it alone gave my patrol 0.5 lph increase in economy also a larger exhaust to help get rid of gasses say around 2 1/2 " Both items will compliment each other and increase power then you will use less accelerator to achieve the same speed and intern use less fuel. Also make sure your tyre pressures are increased according to the weight carried it depends on your knowledge if your clued up that's great or you could ask a tyre outlet for recommedations if your not quite sure.