Cat hides its claws

The engine needed to loosen up a bit but the new 630S was comfortable, efficient and flawlessly finished

Cat’s new 630S is a shortened version of the successful 630LS that is gaining a reputation for guts and dependability. The new model shoehorns the C15 550hp engine into a frame delivering 34-pallet capability on wheelbases from 4800mm down to 4600mm.

It significantly reduces the turning circle, enhancing the truck’s attractiveness for inter and intra-city work. A bonus is the dead-simple emissions-control system. No EGR, no SCR, no AdBlue and none of the excessive heat EGR systems are renowned for.

Previously, you could only get 550 Cat horsepower in a wheelbase that was too long for 26m B-double applications. If you needed something shorter, you had to live with the smaller 13-litre engine which wasn’t built for the heavier-duty tasks.

The 630S is a tighter package and Cat’s new managing director, Kevin Dennis, now says it should have been the first Cat truck released back in 2010.

For my Brisbane-Melbourne drive, Cat had pulled the first production unit off the boat and hitched up a B-double set with about 54 tonnes on board for a gross weight of 62 tonnes. The 630S sported a flawless bronze paint job that stood out like a jewel in the dealer’s yard.

Unlike all the other US-built trucks I have driven, from the driver’s seat the bonnet surface was ripple-free and edges were finished with a quality at least as good as the best passenger cars.

With just 2000km on the odometer, the truck was tight as a drum, which meant the transmission was still very stiff and needed gentle persuasion.

I also have to say this C15 felt a little restrained, particularly on any kind of hill, where other rigs rumbled past with monotonous regularity. I remembered the longer 630LS I drove a couple of years ago felt more lively pulling a double road train at about 80 tonnes.

There is little doubt that with a few months work the C15 will loosen up a bit but in reality the standard spec 3.19:1 rear axle ratio worked against the newest Cat in a role it wasn’t really specced for. With the optional 4.1 or 4.3 rear end, the truck would have cruised at up to 1650rpm and had much more punch in the lower gears.

The Cat impressed on appalling roads down the inside route to Melbourne via Dubbo. The steering managed camber changes, crosswinds, potholes and ripples, all complicated with driving rain for the first part of the drive.

Heading up Cunningham’s Gap, the weight of the load and tall gearing kept the truck in the bottom box, so I got to check out the cab properly. Cat has trimmed the interior with refreshing colours and surfaces. The steering wheel is thick and comfortable, armrests on the inside of the seats complement the side door sills and the touch screen is large and clear, with most digital services. It needs a USB port, though.

My 1700km run returned an impressive 1.55km/litre, verified by on-board monitoring equipment from Procon (see this week’s other Work Wheels story), helped no doubt by the tall diff. But true interstaters will trade some fuel for more urgency.

Bringing the engine closer to the cab has increased driveline noise. Unlike European cabovers, this Cat makes it clear you’re driving a big-block American engine and an Eaton 18-speeder. Gen Y drivers will probably complain but experienced hands will just turn up the country and western.

Source: Page 26, West Wheels, May 3-4, by David Meredith

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