MOLINE, Illinois (March 10, 2015) — The John Deere 550K, 650K and 700K Crawler Dozers not only meet Final Tier 4 emissions standards, but also incorporate value-enhancing features such as Eco mode and an updated electro-hydraulic (EH) control system.

https://www.deere.com/en_US/corporate/our_company/news_and_media/press_releases/2015/construction/2015mar10-k-series-crawler-dozers.page

March 9, 2012

John Deere is adding four models to the K-Series crawler dozer line, providing contractors an emissions-certified machine that affords higher productivity, increased uptime and lower daily operating costs in earth moving and grading applications. The 550K, 650K, 700K and 750K crawler dozers build off the popular and successful 850K that launched in 2011.

A John Deere PowerTech 6.8-L (700K, 750K) or 4.5L (550K, 650K) IT4 (Interim Tier 4) diesel engine provides an increase in horsepower from the previous J-Series, along with increases in overall tractor weight, resulting in more productive machines. The horsepower ranges include: 85 hp (550K), 101 hp (650K), 125 hp (700K), and 155-165 hp (750K) at 1,800 RPM.

https://www.oemoffhighway.com/engineering-manufacturing/press-release/10653769/john-deere-launches-emissionscertified-kseries-crawler-dozers