This mod is Mack E9 V8 Straight pipe sound for Harven's R Series, Dielingwu's Superliner, KSW's Superliner, and BPM's MH613 DISLAIMER: NOT COMPATIBLE WITH ANY SCS'S MACK TRUCKS BY DEFAULT, DEF EDIT WOULD BE REQUIRED Latest Version Feature: -Mack E9 V8 400-