Here is the full list of all 45 Flatout 3: Chaos & Destruction achievements.
Kill 10000 zombies.
Complete all challenges.
Win all Nightshift races.
Complete 25 challenges.
Win all races.
Win all Harbor races.
Win all Uranium Mine races.
Win all Speed tracks
Win all Vienna races.
Complete all stunts.
Win all Outdoor races.
Finish a Nightshift race as loser.
Win all Offroad races.
Win all Kansas Offroad races.
Win all Utah Offroad races.
Win all Monstertruck challenges.
Win all normal Battle Arenas.
Win a Nightmare stunt.
Win all Big Battle Arenas.
Win an Industrial stunt.
Win a normal Battle Arena match.
Complete a challenge.
Win all Rome races.
Play a multiplayer game.
Score a 150 hit combo.
Complete all splatout levels.
Score a 100 hit combo.
Score a 60 hit combo.
Score a 40 hit combo.
Score a 50 hit combo.
Get a score of 7 million.
Be destroyed by a train.
Score a 30 hit combo.
Win all Detroit races.
Win a Big Battle Arena match.
Win on a Speed track.
Win a Golf stunt.
Win on a reversed track.
Win a race.
Win a Nightshift race.
Score a 20 hit combo.
Drive into water.
Win a Monstertruck challenge.
Score a 10 hit combo.
Kill one zombie.