http://www.goauto.com.au/mellor/mellor.nsf/ganews?readform&make=Mercedes-Benz&model=E-class&start=2
In July 2011 Mercedes introduced further
fuel efficiency
measures to its four-cylinder line-up including a
transmission upgrade to a smoother seven-speed automatic,
idle-stop, self-regulating turbo compressor, optimised oil pressure
control and reduced friction in belt-driven components for the E220
CDI and E250 CDI.
The E250 also benefited from the
more efficient gearbox. All three variants got new steering
column-mounted transmission selectors and paddle-shifters.
The improvements were good for up to a 0.7L/100km
improvement in fuel efficiency (on the E220 CDI).
Fuel efficient... this i believed...
but 20km/litre.... a bit hard to achieve leh... also have to
depend on the driving habits....
If you alway turbo.... then even 10km/litre also cannot
achieved.... 
