Other Publications

Construction Industry Poll

In the Magazine

First Run: Deere’s 650D LC and 850D LC excavators

June 12, 2007 |

If there’s one message John Deere wants you to get with its two heaviest D-Series excavators it’s this: They are here to compete in the big dog league.

“More” seems a weak verb when you compare the 850D LC and 650D LC with their predecessors, the 800C and 600C LC. The 650D LC, for example, now has an 80-metric-ton-class undercarriage and is 15 percent larger than the 600C LC. And the 850D LC is 9 percent larger than the 800C, growing from 168,540 pounds to 185,500 pounds. Both machines, aimed at heavy construction and quarry jobs, carry the heft necessary to complete these projects with ease, says Matt Hendry, product consultant, excavators and ADTs, John Deere.

Balanced strength
“The weight is balanced throughout the machines, rather than just on the front and back ends,” Hendry says. “They really scoot for being such big guys and they don’t porpoise.” The machines increased in overall size and digging power so much that the 600C LC and 800C booms, sticks and buckets cannot be used on the D-Series machines.

Three internal boom bulkheads, one located just behind the stick pin, add rigidity and strength. Deere also uses bulkheads in the stick, contending they offer better strength than using thickened side panels. Deere buckets are designed with shimming adjustments to reduce noise and improve life. And Deere is continuing to use D-frame side channels, citing their durability. Starting in May, the company will offer an optional removable counterweight system.

Controllability equals predictability equals productivity
But none of this new heft was gained at the expense of the excavator operator’s mantra: controllability. “The controls are going to sell these machines,” Hendry declares. “The operators I know – and I used to be one – prefer pilot controls over electro-hydraulic controls, simply because they give you more feedback. We call the controllability of these controls predictability. There’s no abrupt movements. Now add speed to that controllability and your cycle times get better.”

The two models use Deere’s Powerwize III engine hydraulic management system for crisp, responsive hydraulic power. The system is designed to optimize the flow rate for whatever function you’re using. “For example, the boom down is almost twice as fast as the 800C,” says Hendry.

THE 850D LC’s arm force increased 23 percent, bucket force increased 25 percent and lifting forces increased by 11 percent from its predecessor. “There’s a dramatic difference in what it will lift,” Hendry says.

The electronic Isuzu engine in both machines is capable of 550-plus horsepower (the 450D LC, 650D LC and 850D LC share the same fully electronic engine model). The 650D LC is rated at 463 horsepower and the 850D LC at 532 horsepower (see chart on page 26 for more specs).