For adding vehicles to gta iv are some different ways.
If you want a simple way, there is a tool " gta iv vehicle mod installer "
It replace vehicles and their codes automatically, but I don't suggest this way.
The best way is add more cars instead replacing. For this way you need " open iv " and windows note pad.
Open IV is for replacing mod files ( wft and wtd ) and note pad for changing handling, vehicle.ide and carcols lines.
For a tutorial how to add extra cars to gta iv ( at most 70 cars you can add ) you can search google or this forum.
If you don't want add cars and you want to replace with game cars this is the way :
Your game should be up to date. ( 126.96.36.199 or 188.8.131.52 )
Download Open IV = http://ntscorp.ru/ov...up/ovisetup.exe
Run it and select your game ( IV or EFLC )
Then you should give program game file directory.
Then you'll see this :
Open "Models" Folder :
Open cdimages folder :
Open vehicles.img folder :
Here is all gta iv vehicles files.
The vehicle that you've downloaded and you wanna replace with one of gta iv cars have two files, one example.wft and one example.wtd. These two files should have a same and and should have one of gta iv original vehicles name. ( ex : both should be comet, comet.wft and comet.wtd )
Now click on "Edit mod"
Now drag and drop wft and wtd files that you've downloaded and wanna replace with an original car in game.
Now we wanna change settings :
Go here : Partition\Program Files(x86)\Rockstar Games\Grand Theft Auto IV\common\data
Find this file : handling.dat
Right click on it and disable read only
Now open the file with note pad and find the vehicle name that you name wft and wtd files. ( I use comet as expample as I've named my wft and wtd comet "
Copy handling code in your downloaded vehicle archive ( should be in readme.txt ) and replace it with code it game handling.dat file :
Do same for vehicle.ide and carcols code.
Cope code from readme.txt in download archive and replace code in carcols.dat and vehicles.ide.
Use a vehicle spawner in game to spawn your vehicle. ( Like simple native trainer )