Motoring journalist Tom Ford recently took a standard BMW 3-Series 320d EfficientDynamics on a road trip to Munich and back to test out Munich-based BMW’s claims on fuel efficiency for its EfficientDynamics models. These models are specially specified to reduce CO2 emissions and improve fuel consumption when compared to the standard versions – so do they deliver in the real world?

Yes. Ford managed an amazing 1013 miles on a single tank of fuel, equivalent to driving from Land’s End to John O’Groats and still having 200 miles range left in the tank.

As I wrote recently, most car manufacturers are now producing equivalent ‘eco’ versions of their main car models (Renault has just launched its greenest model ever). They use techniques such as modified gear ratios, extra aerodynamic bodywork and other changes to achieve this. While some people may dismiss these models as gimmicks, all the evidence suggests that they deliver real world benefits.

Tom Ford didn’t use any special efficiency driving techniques to achieve this result although he did switch off the air conditioning, keep the windows closed and leave the radio off – all techniques that will help fuel consumption. He also limited his motorway speed to around 65-70mph – a little slower than normal (especially in Germany) but still perfectly acceptable and safe.

Ford admits that his techniques will have helped improve fuel consumption but believes that “even driven normally I still think you’re looking at 750-800 miles per fill.” The BMW’s fuel consumption didn’t dip below 65mpg for the entire trip – and reached a high of 75.9mpg – pretty impressive.

Cars like the 320d EfficientDynamics have another attraction, too. Their low CO2 emission ratings mean that they often fall into a lower tax band than the standard versions of the same cars. The 320d EfficientDynamics has a CO2 emissions rating less than 110g/km – this means that road tax in 2010/11 would only be £20 and would be free in the first year of registration (see here for full details of car tax (VED) costs in 2009/10 and 2010/11).

The trip received a full write-up in last week’s Sunday Times, but you can see a video of his trip on Facebook – click here.