Here is the full list of all 42 Gear.Club Unlimited 2 - there are Ultimate Edition achievements.
Complete an endurance race without changing your tires
Reach 400 km/h on the Le Mans circuit
Win the Ford GT40
Own 30 cars
Buy Gustav Reuter's “Koenigsegg Agera RS Custom”
Beat Gustav Reuter
Win Primo Biondi's car
Win Teruko Nakamura's car
Own 15 cars
Win Vassily Rykov's car
Win Payton Hills' car
Win the Porsche 911 Type 930
Win an Endurance Championship
Finish a race on less than 2% fuel
Beat Primo Biondi
Change the look of your Performance Shop
Put 5 stickers on the same car
Install 10 items in your Performance Shop
Buy a category D car
Beat Teruko Nakamura
Earn your first Million Credits
Complete 25 races with no collisions
Buy a category C car
Own 5 cars
Beat Vassily Rykov
Put back a part of lesser quality
Change the rims of one of your cars at least once
Add a body part to one of your cars at least once
Buy a category B car
Visit another player's Performance Shop
Beat Payton Hills
Build the Wind Tunnel
Build the Body Workshop
Change the color of one of your cars at least once
Complete 25 solo races
Join or create a Club
Install 5 parts on your car
Build the Tire Workshop
Drop out of a race
Buy a category A car
Beat Ken Cole
Build the Mechanic Workshop