Four models are added to Deere K Series of crawler dozers: 550K, 650K, 700K and 750K. John Deere PowerTech Tier 4-Interim diesels provide more horsepower than the J Series predecessors: 85 horspower in the 550K, 101 in the 650K, 125 in the 700K, and 155-165 horsepower in the 750K at 1,800 rpm. Engines maintain oil flow to machine systems to enable operation on slopes up to 45 degrees. A hydraulically driven cool-on-demand fan operates only as needed.