It change the look, the wheels and the suspension
Jeep retuned and new wheel maps
Back up your original jeep_civil.sds file and replace.
PLAY!
It's a war hero dlc car so if you don't have the dlc just replace another car (rename).
If you do have the war hero pack just put a 1 in front of the jeep civil.sds in the car file of the dlc and replace or put the new file in the pc/sds/cars folder. There should be a jeep_civil and _z sds files already there. You will just replace the summer car (jeep_civil.sds)
Enjoy
Notice by :Crazypreacher,
if you don't have the war hero pack
Use my other jeep modification and then just drop this file in
C:\Program Files (x86)\Steam\steamapps\common\mafia ii\pc\sds\cars
enjoy