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