Limiting trucks to 52mph saves fuel but there are drawbacks.

With diesel prices at an all time high, hard-pushed vehicle operators are always on the lookout for ways of reducing their costs and limiting speed would appear to be an obvious course of action. 

Although the legal motorway speed limit for vehicles over 7.5 tonnes is 60 mph a European directive which came into force during the 1990s requires them to be limited to 56 mph - 80 kph. However, some transport companies have experimented by further limiting their vehicles to 52 mph in a bid to save fuel.  While there is no doubt that vehicles operating on long motorway routes use less fuel, the drawbacks including longer journey times and safety concerns have caused most operators to conclude that limiting to 52 mph is counter productive as well as being unpopular with their drivers.

Longer journey times mean more wages for the driver and possibly an overnight stay if he runs out of hours on route, which would almost certainly wipe out any savings made on fuel.  Congestion caused by the need for vehicles running at 56 to overtake their slower counterparts at only a 4 mph differential is another problem flagged up by many drivers.  Joining motorways is another concern as it is more difficult to merge with traffic travelling in lane one without causing other drivers to slow down.  However, HGVs working mainly on motorway routes can expect to use up to 18% less fuel by restricting speed to 52 mph, but it’s important to remember the saving can only be made when using the motorway, as speed limits are lower on dual carriageways and two-way roads at 50 mph and 40 mph respectively. Educating drivers to drive more economically may provide a better way of saving fuel overall.

Earlier this year The Mover reported that according to a survey conducted by Volvo, 50% of HGV drivers do care about the amount of fuel they use and drive as economically as they can.  A further 40% said they occasionally considered fuel economy with only a very small percentage of professional drivers giving no consideration to fuel economy at all.  The report went on to say that even experienced drivers can benefit from training in fuel efficient driving to the tune of around 7%, with even greater savings achieved by less experienced drivers.

Top tips for economical driving:

• Get the tyre pressures right;
• Set the vehicle up properly: cab gap, cab deflector and axle/trailer alignment;
• Try to get into top gear as soon as you can;
• Plan ahead, blend in with traffic and try not to come to a complete stop.