Pause the game and enter the following codes under "Bonus Codes" in the Options Menu for the desired unlockable:
- 48992519 — Camo Army Helmet
- 20061977 — Road Addict Jacket
- 07994647 — Sludgeray
Note: If you want a complete score under General Info, Progression, Driver Gear Pieces Owned 78/78, then you will need to activate the above bonus codes.
- 17121973 — Lightning Bolt livery for Mudhog
- 18021974 — Butterfly livery for Sludgeray
- 18041851 — Warrior vehicle