It's working normally. It's a 4-speed tranny that starts in 2nd gear. 3100rpm at 100kmh is what you should expect with a 3.0x differential ratio.

It's starting in 2nd, shifts into 3rd at 30kmh and into 4th at 50kmh.

EDIT: 30 and 50 is somewhat early to shift. I'm unsure of how to adjust the shift points on the 80SD.