There was something called as Left 4 Dead zombie mod for IV that was for 1.0.7.0. Anyhow, theres one zombie mod for 1.0.7.0 with running zombies in This mod pack. Meh police officers become zombies, thanks anyways. Looks like fans are getting quite creative out there with fun new mods using the recently released fan-created ICEnhancer tools for GTAIV PC. Among some of the cool ones we’ve seen, this particular mod pits Niko against waves of bloodthirsty undead.
The advent of next generation systems has taken the virtual reality of video games to a new level by allowing techno-savvy gamers to not just be in a virtual world but to modify it in ways that can completely change its mood. The Zombie Apocalypse Mod for Rockstar Games' 'Grand Theft Auto IV' is an example: Thanks to user jc0001, you are now not just a virtual criminal, but also a heroic fighter of the living dead.
Go to GTAGarage.com (see References for link). If you have an account, log in; if not, it is a good idea create one, though not absolutely necessary.
Click 'Major Modifications.'
Browse the list until you see 'GTA 4 Zombie Apocalypse.' Click that link.
Click 'Download Mod' on the right-hand side of the screen under the screen shots in the 'Files' box. It will open a list of files.
Download the most recent file as this will be the most complete. Once you click the file, a dialog box will open confirming that you want to download it.
If you have a GTAGarage Account, find the mod faster by searching 'Zombie Apocalypse' in the search box in the top right corner of the screen.