This mod is Detroit Diesel DD13/15/16 with stock sound for SCS Freightliner Cascadia, Western Star 49X 
and Western Star 5700XE by Sherman

Version 3.0:
-Rebuilt the entire mod
-Oh the SCS 5700XE is also compatible now
-Ye there's more than 1 changelog now so that's nice

Version 2.0 Changelog:
-Rebuilt the entire mod
-Compatibled with SCS Western Star 57x
-Featured full 3D real directional engine sound for extra realistic 
and different sound from the front and the back of the truck
-Used max volume regulation to reduce chance of sound flickering and prevent too loud sound 
(Highly recommended to put engine, exhaust, turbo volume slider to max)

Version 1.0 Feature:
-Detroit DD13/15/16 with stock sound (DD13 and DD15/16 have different sounds)
-Custom sound attenuation for realistic sound fade off
-Custom sound orientation for realistic sound from different angle
-Custom exhaust distortion for realistic exhaust tone depends on throttle pressed
-Custom interior attenuation for realistic sound inside the truck

Credits:
Slav Jerry - Sound modding
SCS Software - sound samples and engines data