Page 28 - Demo

e Constellation’s cab is a nice working environment – in the classic North American style
barely cover any more than the exterior windscreen visor. So sun- strike is a problem.
In top gear, the Cummins runs at just under 1500rpm at 90km/h, and at all speeds, the cab is impressively quiet. Conversation doesn’t require raised voices.
As the road surface becomes bumpier, the Western Star’s ride quality also becomes rough and lumpy, with jolts transmitted into the cab. In a masterpiece of understatement Woolston says that it’s “not the smoothest ride I’ve had.”
Soon he puts it more plainly: “The biggest disappointment is the ride. It’d be nice if the truck didn’t have to be bouncing around all the time.”
Woolston has no complaints though about the engine: “It’s doing a beautiful job. I have to hold it back from doing 100km/h.” The Western Star climbs the steepest (lower) part of the Tarawera hill in fifth low gear, the Cummins working at 1500 revs and our road speed down to 30km/h.
The engine performance gives Woolston “plenty of time to pick up gears. It pulls quite constant, holds revs really well. It performs
from 1000 to 1500rpm and you don’t have to rush the gears, which is easier on the gearbox.”
Climbing up to the summit, the truck’s back up to 60km/h, in seventh low: “It’s never struggled at all,” says Woolston approvingly.
There is another negative to this test though – the weather! It seriously deteriorates as we head into low cloud that hugs the mountainous terrain. We’re 80-odd kilometres from Napier when the rain really sets in, as we thread our way through the tight and twisty going.
The rain lashes the slightly-curved glass of the split windscreen but the wipers are more than up to the challenge, efficiently and effectively clearing the water and ensuring clear forward vision.
Woolston hands the truck over to Robert at the McVicar Road junction, just on the Taupo side of the testing Titiokura climb. It’s a hill that seems to go on and on...and on. But the X15 hauls the 46-tonne combination up the steep gradient easily.
“The pulling gear for this hill is fifth in the high range of the gearbox – low split...which will take us up the hill no worries,” says Robert.
26 | Truck & Driver