In this section of our website you can download GTA 4 mods - various modifications to improve the graphics and add cool effects, new loading screens and. Plug Your USB into your computer 3. Download and open Horizon 4. Click the USB Icon at the side and find your GTA IV Save 5. Click Mod and. Unlock the Rolled Over Achievement in GTA IV: Achievement Hunter presents this video walkthrough of Grand Theft Auto IV for the Xbox or PlayStation 3. Question, Status. Are you allowed to download mods for GTA IV? Answered. What and where is this car? Answered. What is the Car Wash for? Answered. The GTA IV, developed by Rockstar North was published by Rockstar Games, and GTA 4 xbox and PlayStation 3 were releases on 29th April, It was .