Grand Theft Auto 4 Corruptions
So, this is what the dream feels like...
FAQ:
Q: How are you doing this?
A: I use RTC (Real-Time Corruptor)
RTC download link: https://redscientist.com/rtc
However, some corruptions in this specific video have been done by corrupting the vehicle handling file contained in the game files.
To find this, navigate to where GTA 4 is installed, then go to 'common', 'data', and 'handling.dat' should be there.