OH WHAT a difference 62-tonne makes.
On my drive from Melbourne to Sydney this week in Mercedes-Benz' Actros towing a fully-loaded B-double set, I managed to drive the fuel consumption down to an average 58.3l/100km.
The next day I drove Toyota's latest fuel miser, the Prius V, which managed 4.4l/100km.
But in terms of pure fuel efficiency, the best way to measure the actual fuel cost of moving a load is litres per tonne/100km, which takes weight into account.
The big Merc did its job using just .94 litres per tonne/100km.
While the Prius, at 1705kgs including two adults, could only rate 2.58 litres per tonne/100km, making the truck nearly three times more fuel efficient than the Toyota.
The comparison is mostly pointless but does illustrate how efficient modern diesel engined trucks are at distributing the nation's supplies.
And most times, the larger the rig the better the efficiency.
In the Daimler Trucks world, Actros is the premium model of the premium brand, with all the technology, quality and gizmos to make it the most prestigious purchase in Europe. A new model Actros has just taken out Truck of the Year in Europe for 2012, but nothing will be happening on that score until local testing of the Australian-spec cooling system is scheduled and completed.
So the current Actros is the truck that Mercedes Benz is using to make a move into the huge interstate, multi combination market.
The technological gap between Euro trucks is narrowing, as manufacturers develop emissions systems that are closer in specification. The driver aid picture is also blending and even engine characteristics of the major brands are similar. Mercedes-Benz remains one of the last to build V8 engines for heavy-duty on-highway applications. When new Actros is released, MB will blend into the six-cylinder club, leaving Scania alone.
In the meantime, I appreciated the distinctive rumble of a 15-litre V8 diesel as I started the Actros early one morning in Melbourne. After a few bells, buzzes and flashing lamps, the motor settled into warm-up mode and I got busy outside the cab with my check routine.
The Actros B-double rig was parked in the middle of a yard full of Mercedes-Benz light commercials for the Australian army, so it was a careful start to the day as I weaved around the camouflaged 4x4s, heading for the gate.
But moving off in today's Actros is little different to a car. The transmission selector is a stubby little lever on the front of the left-hand armrest. You just press the release button, click it forward and that's it.
You release the single action park brake, press the throttle and you're on your way. The Actros driving position is pretty much straight up, but the seat is formed well enough to give you the support you need for long distances.
Vision from the driver's seat is excellent - the Actros cab towers over its competitors so it takes five steps to get up into the cab. Mirrors are large and vibration-free, but the dash reflects into the main mirror at night making the bottom half useless.
After clearing Melbourne, I started experimenting with the cruise control and radar-controlled distance system.
The cruise control is an adaptive set-up where you can set the preferred distance from traffic ahead. But it takes a bit of getting used to as the system is blind to road conditions in front of the traffic. And in the Actros, there's not much you can't see over.
Ultimately, to maintain a decent cruising speed and use fuel efficiently, I was using cruise control up long hills and on the flat, then clicking to manual over the crest and downhill.
The Benz Powershift transmission is as quick on the change as any AMT I've driven. Although it only has 16-speeds, with a bit of patience and driving ahead of yourself, you'll quickly find an efficient blend of cruising speed and dealing with the hills.
The engine brake/ retarder lever is a finger-stretch away on the right side of the steering column. Mercedes-Benz plans to push harder this year to get a bigger share of the interstate heavy-duty market.
The Actros specification is quite capable of meeting the needs of almost any long-distance operator, but so far the product hasn't made an impact - we only saw two other Mercs on the drive north.
If dealers are able to get prospects into the Actros for a run, that might change pretty quickly.