I am using a Texas State Troopers pack and want to know how to make regular NPC cops use certain vehicles. I am not afraid of going outsides my mods folder.

The slots regularly used are here.

s_m_y_cop_01

• police
• police2
• police3

s_m_y_sheriff_01

• sheriff
• sheriff2

These values can be changed in the dispatch.meta and I believe in popgroups.ymt. Maybe popcycle.dat.

17 hours ago, TheTechLyon said:

I am using a Texas State Troopers pack and want to know how to make regular NPC cops use certain vehicles. I am not afraid of going outsides my mods folder.

I do as Lundy suggests, however I just go to GTA V/lspdfr/backup and use Notepad++ to edit the values. I currently have all of my city backup replaced with sheriff as the vehicle and s_m_y_sheriff_01 as the ped, because I'm using a sheriff pack. I also replaced all of my State units to only use police4 instead of the bike. The reason I only edit the backup, is because these units don't ever really spawn like they did in GTA IV. They normally only appear when I call for backup. The only exception is 3 units parked on the road in Blaine County, and 2 units that spawn within a block of the Downtown Police Station. Other than that, it's only your backup units and you. It's all entirely up to you 

I instead went in GTAV main directory/lspdfr/data and edited the ''agency.xml'' file, changing the vehicles they use. Here's an example.
<Agency>
        <Name>Los Santos Police Department</Name>
        <ShortName>LSPD</ShortName>
        <ScriptName>lspd</ScriptName>
        <Inventory>default</Inventory>
        <TextureDictionary>web_lossantospolicedept</TextureDictionary>
        <TextureName>web_lossantospolicedept</TextureName>
        <Loadout>
            <Name>Patrol Unit</Name>
            <Vehicles>
                <Vehicle>police</Vehicle>
                <Vehicle>police5</Vehicle>
                <Vehicle>police7</Vehicle>
            </Vehicles>