VIVA ENERGY, the licensee of Shell products in Australia, had a theory they wanted to test.

If they ran a truck on synthetic lubricants instead of mineral grade lubricants, would the truck use less fuel?

The results, which they revealed to TMC delegates in Melbourne, were unprecedented, pointing to a potential fuel economy benefit of up to 2.5%.

That’s a massive difference to any operator’s bottom line.

To go about proving the numbers, the Viva team, which included our very own Diesel Doctor (see page 12 for his latest column), Paul Smallacombe, Viva Energy’s product support engineer, left nothing to chance.

They even ensured the truck they used was plucked from a working fleet, rather than a new one, opting for a Western Star 5800 SS Prime Mover with a 14.8 Detroit Diesel DD15 engine (560hp).

“Our Shell Lubricants team devised a wide-ranging research study that was totally focused on Australian driving conditions,” said Mr Smallacombe.

First up, Melbourne based Kangan Institute Automotive Centre of Excellence was engaged to supply the chassis dynamometer together with expertise on the operation of the sophisticated dyno. The transient drive cycle selected provided a representative mix of Australian congested city, urban fringe and highway driving.

Secondly, it was decided that the test should be conducted by a specialist transport research company and ABMARC was chosen. ABMARC is an independent Australian company with a team of highly experienced engineers and research staff who deliver a broad range of services to the transport and energy sectors. ABMARC are specialists in precisely measuring fuel efficiency improvements and have a long history of similar projects in industry.

A comprehensive testing program consisting of multiple repeats of drive cycles, with the engine starting form a warm condition was the overall strategy. The drive cycle used in the testing is an Australian based drive cycle, reflecting the driving conditions that a typical truck operator would experience on the road in Australia. It consists of a mix of metro stop-start, outer urban and highway running to reflect road conditions.

The impact of changing the lubricants was assessed based on fuel consumption in transient conditions, simulating driving the heavy duty on-highway truck in an Australian environment.

The fuel measurement system was connected to the three fuel lines and this allowed the net fuel consumption to be measured with a single fuel flow meter, improving test measurement accuracy and repeatability.

To simulate the test vehicle towing a laden trailer and provide the most realistic indication of the fuel consumption in the real world, the maximum inertia possible was simulated by the dynamometer whist minimising tyre slippage on the rollers. The simulated vehicle inertia was 25,000kg. This represents the gross vehicle mass simulated through the testing.

Critical to the testing regime outcomes were the Shell Transport Lubricants used. Test cycles were undertaken with mineral oils and repeated with synthetics.

“The fuel consumption saving results achieved in the testing were impressive. The Shell Synthetic Lubricants range of products performed faultlessly throughout the testing regime and this research offers real substantive benefits to the Australian transport industry,” concluded Paul Smallacombe. “A 2.5% reduction in one of the largest cost components of transport operators is significant.”