Here is the full list of all 28 On The Road - there are Truck Simulator achievements.
Create a second savegame
Hire the first driver for your company
Entirely fill your tanks.
Reach Level 1
Reach Level 3
Reach Level 7
Reach Level 10
Hire three drivers for your company
Hire six drivers for your company
Own two motor vehicles and two trailers
Own three motor vehicles
Own five trucks and five trailers
Own nine trucks and nine trailers
Buy a drawbar trailer
Buy a tandem trailer
Buy a semi trailer
Buy a gigaliner roadtrain combination
Own one motor vehicle with a mileage of at least 10k kilometres.
Own one motor vehicle with a mileage of at least 100k kilometres.
Own one motor vehicle with a mileage of at least 500k kilometres.
Get caught by speed camera
Deliver an assignment without any damage
Deliver an assignment with max 10% damage
Deliver an assignment with max 50% damage
Deliver an assignment with full damage.
Combine enough assignments to reach 50% of your vehicles maximum payload
Combine enough assignments to reach 70% of your vehicles maximum payload
Combine enough assignments to reach 90% of your vehicles maximum payload