Here is the full list of all 43 WRC 8 achievements worth 1,000 gamerscore. It takes around 40-50 hours to unlock all of the achievements on Xbox One.
Changed team 5 times
Participated in 50 events in the calendar
Reached level 40
Reached the podium in the Rally Turkey in Career mode
Won a first Stage in online Multiplayer mode
Reached the podium in the Rally Italia Sardegna in Career mode
Reached the podium in the XION Rally Argentina in Career mode
Won a rally with a repair time penalty
Won 25 Stages
Won a Historic Race event
Won a rare event
Won a Stage with a car that has not been repaired
Obtained a DNF in any mode
Reached level 20
Reached the podium in the COPEC Rally Chile in Career mode
Won 15 Stages with dynamic weather in Quick Play mode
Reached the podium in the Rally Sweden in Career mode
Reached the podium in the Rally Monte Carlo in Career mode
Crossed 200 water puddles
Joined the WRC 2 Championship
Reached the podium in the Neste Rally Finland in Career mode
Started a new career in WRC 8
Rolled a car over in any mode
Win 50 Stages
Win 100 Stages
Win 10 Stages at night
Complete a season objective
Complete 15 objectives of any type during the same season
Win a Stage in Authentic difficulty
Become WRC World Champion
Reach the podium in the Corsica Linea - Tour de Corse in Career mode
Reach the podium in the Rally Guanajuato México in Career mode
Reach the podium in the Vodafone Rally de Portugal in Career mode
Reach the podium in the ADAC Rallye Deutschland in Career mode
Reach the podium in the RallyRACC CATALUNYA-COSTA DAURADA in Career mode
Reach the podium in the Dayinsure Wales Rally GB in Career mode
Reach the podium in the Kennards Hire Rally Australia in Career mode
Reach the podium in all rallies in Career mode
Use 15 Perks
Have 4 legendary cards in an active crew
Drive over 500km in any mode
Drive over 1,000km in any mode
Drive over 2,000km in any mode