Here is the full list of all 28 Zombieland: Double Tap - Road Trip trophies - there are 8 bronze, 13 silver, 6 gold and 1 platinum.
Earn all other trophies.
Earn ZKOTW 12 times
Gain a kill with every environmental hazard
Beat a level with 4 players, each playing a main character
Collect 100 Twinkies to celebrate 100 years of Hostess!
Beat all the side missions
Fully upgrade Weapon Durability
Fully upgrade Speed
Fully upgrade Special Meter
Last 88 minutes in a single Horde Mode
Kill six zombies and light yourself on fire with a single Molotov
Fully upgrade Health
Travel from L.A. to D.C. in under 5 hours and 45 minutes
Beat the tenth level
Kill one of every zombie
Earn a kill with every weapon
Beat the ninth level
Beat the eighth level
Beat the seventh level
Fully upgrade Weapon Damage
Beat the sixth level
Beat the fifth level
Beat the fourth level
Beat the third level
Beat the second level
Beat the first level
Kill four zombies with one shotgun blast
Kill three zombies with one sniper rifle shot