For those of you wondering why the game claims to have 19 trucks but only 15 are availiable to choose from, 4 trucks are hidden and can spawn in maps (crossing seems to have all of them, for me at least). The 4 hidden trucks are:
C-65115, which is the highway version of the C-65111 with highway tyres, less ground clearance and no diff lock/AWD. This means it isn't very useful off road so only seems to spawn on maps near tarmac roads.
D-535, which is a less powerful version of the D-537, with a shorter chassis and a longer engine area with different vents. This truck was availiable in the original spintires.
A-968M, which is the car. There are two versions, a blue and a beige one. Not really useful for much, only seems to spawn on maps near tarmac roads.
C-4320, which is a beige version of the C-375 with a different bumper, grille and headlights.
Just thought people might find this interesting.