Liebherr has introduced two Tier 4-Final crawler dozers, the PR 746 Litronic and PR 756 Litronic, joining the PR 736 introduced at Bauma last year.
The PR 746 Litronic is a 252-horsepower unit, and the largest of the company's "Generation 6" dozers, the PR 756, has an output of 340 horsepower. The main components of the new crawler tractors come from Liebherr's own production facility. Among these are the diesel engine and the common rail injection system, as well as the hydraulic and electronic components. These are adapted optimally to the requirements of the machines, Liebherr says.
Key features include a newly developed, electronically controlled drive management with integrated ECO function. This enables the operator to choose between high performance and maximum economy. Compared with the previous generation, the ECO control system ensures more efficient operation of the travel drive for light to medium-heavy operations. Another new feature of the Generation 6 crawlers is the proactive power control. In this instance, internal engine parameters as well as external machine parameters are detected, such as the current degree of drive joystick deflection, resulting in engine performance being elevated automatically for a short period to match the current demand. As well as responding more rapidly, the machines offer a tangible increase in performance potential and pulling power, according to the company.