Hint
If you are getting beat up by the swarm of cops that come out in full RIOT, go to the garage and park. The RIOT will be turned off. To save your progress, you will have to pull into the garage again.

Easy kills
If a gang of cops or rival gangs are coming after you, learn to drive and shoot in reverse. Back away from the cars about to explode or it will take off a lot of armour.

Faster Upgrades
Stay by your garage and induce a RIOT by killing the civilians and other gangs. To get a RIOT faster, blast away the street cops. When your armor is running low, drop by garage and get repair kit. Repeat until you have enough money to upgrade. If you fail, do not start by loading the previous game. This will allow you to keep the money, no games penalites and you can keep your upgrades. You will only lose weapons.

Other towns
When you progress enough, you will be taken to another city by following the "M" on the map. You can actually go back to the previous city at anytime. Pay attention to where exits are for the cities.

PS2 Cheats for Roadkill

Roadkill cheat codes

Roadkill cheats