Create a backup copy of the CONFIG.CFG file in "C:Program Files Hard Truck 18 Wheelsgameusr" by renaming it with "old" as "OLDCONFIG.CFG". Now edit the CONFIG.CFG file in Wordpad or a similar text editing program. Find the line "uset g_console" and change the number 0 to a 1. This will switch on the debug/game console. Save the COINFIG.CFG file.
Start up HT10WoS, then press the ~ (tilde) key to display the console when you're in the game. You can now type in the following cheats:

To change the truck, use one of these:

Cheat truck 1
Cheat truck 2
Cheat truck 3
Cheat truck 4
Cheat truck 5
Cheat truck 6
To change your rating, use:

Cheat skill 1
Cheat skill 2
Cheat skill 3
Cheat skill 4
To set the amount of money you got, use:

Cheat money X (replace X with the amount of money you want)
To resume play and close the console, just hit ~ again.