The official GTA 4 game has no built-in trainer. The only trainers are mods. So if you’re using a mod menu like (less common), check its documentation for rebinding. Most modern trainers for GTA 4 Complete Edition (patch 1.0.7.0 or 1.0.8.0) support .ini rebinding. If yours doesn’t, switch to Simple Native Trainer v6.5 or newer, as it has the most comprehensive key remapping.
Most gaming laptops have a numpad embedded into the main keyboard, usually activated by holding Fn (Function) and pressing certain keys (e.g., Fn + U = Numpad 8, Fn + J = Numpad 2, Fn + K = Numpad 6, Fn + H = Numpad 4, Fn + I = Numpad 5, Fn + M = Numpad 0). Check your laptop’s user manual. If this works, you don’t need any modifications—just hold Fn while pressing the corresponding letter keys. Unfortunately, this is awkward for fast-paced trainer use, but it's an option. gta 4 trainer no numpad
; Map P to NumpadSubtract (slow down) P::NumpadSubtract The official GTA 4 game has no built-in trainer
; Map I to Numpad0 (back) I::Numpad0
; Map O to NumpadAdd (speed up / teleport) O::NumpadAdd Most modern trainers for GTA 4 Complete Edition (patch 1