PAYDAY 3
PAYDAY 3 runs on Unreal Engine 5. Modrex installs all three of the shapes its mods come in.
Launchers
| Launcher | Support |
|---|---|
 Steam |  |
 Epic Games | |
 Xbox App | |
Mod targets
| Target | Path under game folder | Notes |
|---|---|---|
| Pak mods | PAYDAY3/Content/Paks/~mods | Primary target for pak files, including the .ucas and .utoc a container mod ships beside its pak. Disabled files are kept under disabled with a .disabled suffix. |
| UE4SS mods | PAYDAY3/Binaries/Win64/UE4SS/Mods | Used for Lua mods, inside the UE4SS folder the loader reads. Modrex excludes bundled UE4SS framework modules from the installed list. |
Mod formats
Section titled “Mod formats”Container mods ship three files that belong together: a .pak, a .ucas and a .utoc
sharing one name, usually ending in _P. They replace the game’s own art, models and interface.
Modrex keeps the three together through every install, move and removal, and keeps the name the
author gave them, because the game reads that name: a container renamed away from its _P stops
overriding anything.
Single pak mods are one .pak on its own, most often replacing sounds. Still current, and
nothing about them changed with Unreal Engine 5.
UE4SS mods are folders of Lua scripts. They need the UE4SS loader, and Modrex installs them into the folder that loader reads.
If you copy a container mod in by hand, copy all three files. Two of the three is a mod that silently does nothing.
UE4SS is required for any pak mod to load, not just Lua mods: it carries the bypass that lets the game accept files it did not ship. Install it from its mod page like any other mod and Modrex recognizes it.
A launch option is no longer part of this. Unreal Engine 5 ignores the -fileopenlog argument
older guides ask for, and nothing needs to be set in Steam, Epic or the Xbox app.
Priority
Section titled “Priority”For pak mods, Modrex writes numeric filename prefixes so your visual priority order is reflected on disk. Directory-based UE4SS mods are not renamed for priority.