Liebherr XPower Loaders Deliver a Standard Power-split Transmission & 30% Fuel Savings

New Tier 4 Final Xpower wheel loaders combine the benefits of hydrostatic and mechanical transmissions as standard and at no extra cost to customers

November 4, 2015

Becky Schultz

Liebherr presented a significant advancement in wheel loader design to the 40+ editors from 13 countries in attendance at the annual Liebherr Information Tour, held this year at the Liebherr-Great Britain headquarters in Biggleswade, UK. The XPower Tier 4 Final large wheel loaders, ranging from the L 550 to the L 586, represent what the company describes as the “future of wheel loader technology.”

“XPower is more than just a new machine,” says Martin Gschwend, managing director sales, Liebherr-Werk Bischofshofen GmbH. “It is a comprehensive, innovative machine concept that has the new power-split, Stage IV/Tier 4 Final-compatible XPower drivetrain at its heart.”

Power Split Delivers Best of Both Worlds

The power-split driveline combines both a hydrostatic and a mechanical drive into one system. “Hydrostatic drive is the most efficient at going slow into the pile and the mechanical drive for going fast uphill,” notes Mark Walcher, product manager, wheel loader, Liebherr-Werk Bischofshofen GmbH. “[The power-split driveline] means the power of the engine is going in two paths, so there is less stress on the transmission, which increases its lifetime significantly.”

“The new drive system is powered through the interaction of the two drive paths with the performance and torque of the diesel engine always distributed along both paths,” Gschwend elaborates. “The load is therefore also distributed over the two drive paths, which results in a much longer component lifespan.”

The transmission gearbox manages the interaction of the two drive types, seamlessly adjusting between drives based on the application. “It is adjustable and continuously adapts the mixing ratio of the two drive paths without noticeable switching and without interrupting traction power,” says Gschwend. “In this way, the power of the wheel loader adapts to the specific requirements of the particular operation. The machine is always optimally powered to ensure maximum productivity.”

The loaders are powered by 191- to 354-hp Tier 4 Final diesel engines featuring Liebherr-developed selective catalytic reduction (SCR) technology that does not require a diesel particulate filter or exhaust gas recirculation. While the engines operate at a low 1,100 to 1,300 rpms, they deliver the power needed for optimal performance but with lower fuel consumption.

Control of the driveline is managed by Liebherr Power Efficiency “intelligent” software. “Liebherr Power Efficiency coordinates the engine and transmission with the hydraulic components so we are able to get much more fuel efficiency,” says Gschwend. “Our comparative tests have shown that Liebherr XPower wheel loaders require up to 30% less fuel than conventionally driven wheel loaders.”

Admittedly, the power-split driveline is not a new concept. However, the XPower models represent the first time it has been made standard on a wheel loader. “We have it as standard and we developed it together with our gearbox supplier to ensure integration into our machines,” Gschwend notes, adding that it comes with no price increase over the previous generation beyond a 1% inflation increase. “The price increase for the system itself is zero.”

Designed to Be Dependable

According to Gschwend, “The main objectives in the development of the XPower have been fuel efficiency, robustness, power, maximum performance and comfort." Consequently, design changes have extended to other areas of the machines.

XPower models are equipped with stronger axles compared to previous generations, in part by fitting models with axles from the next size up. For example, the L 556 XPower is equipped with axles previously used on the larger L 566. “Component layout has also been improved to increase strength and reliability and the safe and versatile use of the components,” says Gschwend. "Other core components have also been strengthened. For example, larger bolt diameters and an optimized lever ratio have been introduced to increase the lifespan of the lift arm."

"The new wheel loaders have almost no brake wear as the XPower drivetrain independently supports braking so that the operating brake has only a support function," Gschwend continues. In addition, the standard automatic self-locking differential minimizes tire wear by providing tractive force when it’s needed. “Tire wear is reduced by up to 25% as the continuous force control in combination with the automatic self-locking differential prevents the wheels from slipping.”

Other features and enhancements include:

Choice of revised Z-bar with 20% higher breakout force or industrial lift arm linkage (at no added cost)
Revised bucket design with higher volumes and reinforced structure and bearings
Tapered engine hood that opens backwards to serve as an integrated pedestal and provide free access to the engine
Radiator located directly behind the operator cab for more efficient cooling
Center of gravity shifted behind the rear axle, eliminating the need for added counterweight and enabling higher tipping loads
Spacious, ergonomically designed operator cab with all-around visibility, adjustable, intuitive controls, adjustable steering column and high-visibility, touchscreen display with integrated rearview camera

Prior to their reveal to the international trade press and product demonstration at a C&D recycling center located near Glasgow, Scotland (owned by Regart Contracts Ltd.), the XPower wheel loaders were subjected to 65,000 operating hours of testing in a range of challenging and varied applications. Their official global introduction is scheduled for bauma 2016, to be held in Munich, Germany, in April 2016. Introduction in overseas regions will be staggered, with availability in North America possible by mid year.

L 550 to L 586 XPower Key Specifications: