The Harley-Davidson Milwaukee-Eight engine is the ninth generation of "big twin" engines developed by the company. The Harley-Davidson Milwaukee-Eight engine new one is the ninth generation of "big twin" engines developed by the company, but only Harley's third all-new Big Twin in 80 years, first introduced in 2016.Here I perform a 15000 Mile engine oil change on my Harley Davidson M8 Softail and discuss various points .