This is a rare bug, but you can check it by going to in the game menu. Ensure "Auto Save" is manually toggled ON (Green).
: A mismatch between local cache configurations and the Steam Cloud repository can overwrite or erase career profiles mid-session. Method 1: The Modern Steamworks Fix (Complete Edition) dirt 3 autosave fix full
If the quick fix failed, Windows is actively blocking the save. You need to disable "Controlled Folder Access" and force admin rights. This is a rare bug, but you can
Sometimes, the save folder is read-only. Navigate to Documents\My Games\DiRT3 and ensure the folder isn't set to "Read-Only." Method 3: Install/Update Games for Windows Live Method 1: The Modern Steamworks Fix (Complete Edition)
Before applying the fix, you must understand why DiRT 3 is so broken regarding saves. The game acts as a bridge between three pieces of software that no longer play nice together:
Dirt 3 – How to Fix Crash on Startup – Complete Tutorial