I made this modification by editing the GTA SA files. This modification changes the vehicles that spawn in the normal traffic(cargrp.dat) making the traffic more realistic.

---
Features:

- More types of cars are added to traffic.
(rare vehciles spawn in traffic: Phoenix, bullet, hotknife, etc)

- Realistic traffic in every type of regions and zones.

- Trucks, Vans, and buses spawn in traffic more commonly.

- Turcks and vans spawn almost everywhere.

- Decreased commercial and utility vehicles in indutrial zones
(civil cars will also spawn in industrial zones)

- More types of cars spawn in Forest zones.

- Tractors and bikes are removed from forest regions.

- More types of cars spawn in desert regions.

- Monster trucks and dune truck spawn sometimes in desert regions now.

- Gangs and mafias use more types of cars.

---
Last Realistic Traffic update

---
Sorry for my English, and If you have questions or problems, ask me in the comments in gta inside please.

---
Thanks To developer!
Fd030501, for the work.