Boral turns to Allison fully automatic transmissions

Boral Transport’s new fleet of heavy-duty Western Star trucks have been fitted with Allison fully automatic transmissions, which are assisting in lowering trip times, improving truck uptime and providing more efficient operation.

“Our Allison fully automatic equipped trucks are proving to be better in city traffic than automated manuals, with improved trip times coming as a result of quicker acceleration and an ability to keep up with traffic flow,” said Boral Transport’s fleet engineering manager, Merv Rowlands.

“We can have two identically laden trucks leave a quarry 100km north of Sydney at the same time travelling together on the F3 Freeway. When they hit the edge of the metro area at Hornsby, the Allison equipped truck really shows its acceleration advantages, leaving its competitor behind.”

Boral operates hundreds of heavy trucks across Australia in a range of configurations including prime movers hauling tippers, powder tankers, bitumen tankers, tipper dog units and concrete agitators. The company has historically specified Allison transmissions in its large fleet of concrete agitators; however, it had never used Allison equipped heavy-duty trucks with gross vehicle weights in excess of 42 tonnes.

In 2009, Boral purchased three Western Star 4800FX tipper dog vehicles equipped with Allison 4500 Series transmissions to trial the trucks in day-to-day city-based operations. The availability of the Allison 4500 series as a standard option with Western Stars was a significant factor in the choice by Boral as a preferred supplier of heavy vehicles. Following the success of those trials, the company has added five more Allison equipped Western Star tipper dog vehicles in the first six months of this year, and ordered a further 14.

Merv added, “We were eager to try Allison transmissions in city-based vehicles because of our extensive experience with them in agitator trucks over many years and the great success we had with a recent retrofit into a tipper and dog vehicle.

“We always wanted to run these trucks with two different shift patterns to allow us to maximise efficiency when the vehicles were running unladen. Initially we did this by interfacing with our onboard load sensing equipment which could identify whether the truck was loaded or not and switch the shift program accordingly.”

He continued, “Allison’s engineering team then suggested we try the LBSS program, and it worked well, which has led us to use it across all of our Allison equipped trucks.”

Allison’s LBSS (Load Based Shift Scheduling) adjusts the transmission shift schedule to best match the current vehicle load and operating conditions. This is achieved by monitoring vehicle throttle/engine torque demand and the vehicle acceleration rate. When light load conditions are identified, shifts are adjusted to ensure engine RPM is maintained at the most efficient point. When the load is increased or grades are encountered, the shift schedule is adjusted to provide the operator with maximum performance.

“Reduced trip time, zero downtime, improved driver comfort and safety and outstanding performance both laden and unladen are all advantages with the Allison equipped trucks.”