Installation:
1. First of all you'll need modloader which you can find here
- https://www.gtagarage.com/mods/show.php?id=25377

2. Put the Mod inside the modloader folder.

3. Enjoy! (In the handling.cfg file (which is located in your data folder), replace the transmission to 1 for the cars that use the sound file for the best experience)

Ps: The mod originally replaces the slamvan sounds, but you can rename the bank folders to something else.
Here's the list: 
    Bank_001 & 002 - Bravura, Cadrona, Elegy, Euros, Merit, Mesa, Nebula, Previon, Primo, Solair, Uranus, ZR-350

    Bank_010 & 011 - Bullet, Glendale, Trashed Glendale, Oceanic, Tornado

    Bank_019 & 020 - Cabbie, Fortune, Intruder, Picador, Sunrise, Vincent, Willard, Yosemite

    Bank_026 & 027 - Bus, Coach, DFT-30

    Bank_028 & 029 - Broadway, Hermes, Remington

    Bank_031 & 032 - Alpha, Buffalo, Hotring Racer, Hotring Racer A, Infernus

    Bank_034 & 035 - HPV1000, Wayfarer

    Bank_039 & 040 - Blade, Buccaneer, Clover, Sabre, Savanna, Stallion, Voodoo

    Bank_041 & 042 - Quadbike, Sanchez

    Bank_055 & 056 - Kart, Mower

    Bank_057 & 058 - Caddy

    Bank_062 & 063 - Combine Harvester

    Bank_064 & 065 - Bloodring Banger, Monster, Monster A, Monster B

    Bank_069 & 070 - BF Injection, Hotknife, Hustler, Slamvan

    Bank_074 & 075 - Barracks, Dune, Enforcer, FBI Truck, Flatbed, S.W.A.T., Trashmaster

    Bank_077 & 078 - Benson, Cement Truck, Dumper, Fire Truck (both types), Linerunner, Packer, Rhino, Roadtrain, Tanker

    Bank_080 & 081 - Admiral, Elegant, Emperor, Police (all 3 types), Premier, Sentinel, Stafford, Stratum, Stretch, Sultan, Taxi

    Bank_082 & 083 - Dozer, Tractor, Walton

    Bank_086 & 087 - Blista Compact, Club, Esperanto, Feltzer, Flash, Jester, Majestic, Tahoma

    Bank_088 & 089 - Bobcat, Greenwood, Manana, Moonbeam, Perennial, Regina, Romero, Sadler, Trashed Sadler, Tampa, Virgo, Washington

    Bank_092 & 093 - FBI Rancher, Huntley, Landstalker, Patriot, Rancher (both types), Ranger, Sandking

    Bank_094 & 095 - Hotring Racer B, Phoenix, Windsor

    Bank_096 & 097 - Banshee, Cheetah, Comet, Super GT, Turismo

    Bank_108 & 109 - Bandito, FCR-900

    Bank_118 & 119 - BF-400, NRG-500, PCJ-600

    Bank_130 & 131 - Ambulance, Berkley's RC Van, Burglar Boxville, Burrito, Journey, Mule, Newsvan, Pony, Securicar, Towtruck, Utility Van

    Bank_133 & 134 - Freeway

    Bank_135 & 136 - Regular Boxville, Camper, Hotdog, Rumpo, Yankee 