Three new John Deere crawler dozers--the 450J, 550J and 650J--have the performance needed to accomplish the toughest jobs, with numerous design enhancements compared to the prior line.

A key feature of the new J Series machines is a standard, infinitely adjustable blade pitch link. With only one wrench, the blade cutting edge angle can easily be adjusted to any position from 52 to 60 degrees to match machine applications and soil conditions.

The J Series machines continue to use the same engine as the previous line - John Deere's PowerTech 4045T. The oil change interval has been increased to 500 hours. Other engine advantages include a wet sleeve cylinder that provides quieter operation, improved cooling for longer service life and simplified design; electronic fuel control for precision and increased reliability; a low rated engine speed for longer service life; a self-adjusting belt tensioner that reduces maintenance cost; and a coolant recovery system that simplifies maintenance and reduces cost.

The dual path hydrostatic drive transmission provides infinite speed control, a power management system, live power turns, counter-rotation, dynamic braking and automatic tracking control. The Speed-in-Grip (SIG) transmission control system, standard on J Series dozers, features an increased number of user definable rates, allowing greater flexibility to tailor the operating characteristics of the machine to the operator's preference. New adjustable items include a decelerator mode that allows the decelerator pedal to decrease engine speed and transmission speed, or transmission speed only; as well as an option to change operating speed ranges best suited for specific customer applications.

Another new feature on the transmission controller will display the hours and miles of operation of the machine in forward and reverse, which can help the equipment owner understand and manage undercarriage wear. Thirty-three additional features of this transmission controller allow technicians to access quick on-board diagnostics without connecting a laptop computer. In addition, charge pressure and temperature now are monitored by the transmission controller, providing automatic transmission protection.

New, bent axis hydrostatic motors on the J Series machines provide improved transmission control and smoother speed changes. Increased torque capability allows the transmission operating pressure to be decreased, which can improve hydrostatic component reliability.

The decelerator pedal has been enhanced to improve machine control and match it to the operator's preference.

Several new features of the cab and controls improve convenience and comfort. Cab doors open easily with new pull handles, and a redesigned instrument panel and metal dash have backlit rocker switches to improve switch identification in low light conditions. The engine speed now is infinitely controlled with a simple rotary dial, eliminating the need for the throttle lever, linkage and cable. The J Series spring applied-hydraulically released park brake is controlled by the transmission electronic control system, and a new park lock lever reduces effort dramatically to increase ease of operation and improve operator comfort. A 12-volt power port is standard equipment for the operator's personal accessories.

Standard lighting on the J Series includes two grille mounted lights and one rear light. Optional high intensity work lights include two forward lights located at the top of the operator's station and two additional rear lights located at the rear of the operator's station - this increased lighting option allows a machine owner to extend the workday beyond normal daylight hours.

Another feature to extend the workday includes an increased fuel tank capacity for the 450J to 47 gallons, the same as the 550J and 650J. This larger tank will reduce the frequency of refueling for those equipment owners who operate extended shifts. Frame modifications made to accommodate the larger fuel tank on the 450J provide increased operator visibility and easier cleanout around blade lift cylinders. The 650J LGP undercarriage now features a seven-roller track frame, resulting in 92 inches of track on the ground - five inches more than the previous model - for increased stability and productivity.

Source: John Deere, Aug. 3, 2004