How can I change the audio on my car?
If wanting to change the audio for a default slot, such as police, police2, etc: In OpenIV, navigate to mods-->update-->update-->common-->data-->levels-->GTA5.
If you're wanting to change the audio for a standalone car, navigate to where you installed the meta for that car.
Extract the vehicles.meta to your desktop.
Open the file, and find the line of the vehicle you want to modify. You'll see this line:
<audioNameHash />
Rockstar has set it up to where the vanilla slots don't need to have anything else there for the namehash. I'm not sure how that works exactly. For standalone cars, if it just has <audioNameHash />, the vehicle will not have any sound at all. For most people, they never touch the audio name hash and stick with default sounds. However, it's really awkward to drive around a Tahoe and have it sound like a Vic, right? Below I'll list the proper way the namehash should look when you edit it, and then I'll include a list of cars you can put in the namehash to make your vehicles sound more realistic.
Contrary to what some people might think, if you have ELS, you can use civilian car names in the audio name hash. However, you will also have the normal car radio activated. The only way to fix this is either turning the music all the way down/off, or going in the options menu each time and changing the radio to off. Before we continue, I need to point something out. If you are not using ELS, this guide won't be as beneficial to you. The audionamehash dictates how your vehicle sounds and if it has a siren. If you change the namehash to anything but a police car, you will no longer have emergency services capability in your vehicle.
If you're looking for a specific vehicle, you can search using CTRL + F and enter keyword.
This is how it should look once you've edited it: <audioNameHash>police</audioNameHash>
Crown Vic
police
stanier
Dodge Charger
2010 and under (or using the old body style), use police2
2011+ Charger, windsor
Ford Taurus/Caprice/Impala
fugitive (I personally prefer this one. Sounds a lot meaner)
police3
schafter3
Ford Explorer
gresley
nightshark
Chevrolet Tahoe
baller
Ford Expedition
fbi2/sheriff2/pranger (all three of them are essentially Expeditions, so take your pick)
granger
nightshark
Chevrolet Silverado / Ford F-150 / Ford F-350
bison
sadler
sandking (this might work better for the F-150, 350s and Raptor)
Dodge Durango
baller
gresley
nightshark
Dodge Challenger
gauntlet
gauntlet4
Ford Mustang
dominator
Ford Fusion
tailgater (fugitive can also work, it depends on your taste)
BMW Motorcycle
hakuchou
Harley Davidson Electraglide
wolfsbane
Chevrolet Corvette
coquette
Chevrolet Avalanche
There is not currently a GTA version of the Avalanche, so you can refer to the suggested audio for Chevy Silervado, or play around with it and find one you prefer.
Chevrolet Camaro
gauntlet
Dodge Magnum
windsor
gauntlet4 (if newer version of the Magnum)
gauntlet (if older version)
nightshark
If you think a certain namehash works better with "blank" car, send me a PM!