The Cobra technician fitted the speed limiter in less than an hour. The unit is no bigger than an iPhone and can be set at whatever speed is required. There is no cutting into wiring systems and everything is tucked away under the dash where the driver can’t tamper with it.

While many fleets opt to set a 70mph limit (some even choose 80mph, claiming it allows drivers breathing space to overtake), those whose vans do more urban mileage often choose a lower limit, sometimes as low as 56mph. We opted for 56mph to see just how the savings ratchet up compared to travelling at (not over) the motorway speed limit.

The route

Then it was off on two laps of the parkway circuit round our home city of Peterborough followed by a few round-town miles and then a 110-mile haul down the A1M, A14, on to the M11, M25 and finally the A127 to Southend – and back again.

This route gave us an ideal mix of urban, semi-urban and motorway and, with two drivers, we split the journey.

Then the limiter was removed and we did the same trip, only at normal motorway speeds. A glance at the comparison table below reveals the truth. With the speed limiter on, we achieved 43.91mpg – an amazing feat in itself as this van has an official combined mpg figure of 36.2mpg – but with no speed limiter and driving normally, the figure plummeted to just 32.01mpg.

Roughly translated, this means we used 37% more fuel without the speed limiter – which cost an extra £14.07 on this trip alone.

On the time front, the long haul from Peterborough to Southend took a mere 20 minutes extra (two hours 20mins, compared to two hours) with the speed limiter fitted – equivalent to a 17% increase.

For fleets concerned about packing in daily deliveries, this might be too much; but from a fuel saving perspective, the figures speak for themselves.

The results
Miles travelled Fuel used (litres) MPG
With limiter 260 26.93 43.91
With limiter removed 260 36.98 32.01

The Fleet Van verdict

Admittedly governing a panel van down to 56mph is an extreme thing to do, but the fuel savings shown here prove beyond doubt that every fleet operator should be assessing whether or not speed limiters should be fitted to their vans.

The fact that the two testers here both enjoyed the experience after a short while should put paid to any fears about driver acceptance.

Our advice would be to start with a 70mph limit on all vans.

If this doesn’t produce the fuel savings and safety improvements you expect, then try knocking them down bit by bit until your goals are achieved. Once they are fitted, it’s a simple matter to change the speed.

Journeys will take a little longer admittedly but often this problem can be overcome by looking at your journeys and re-arranging them in a smarter order.