Pre-NAMUX Harnesses

Kustom Truck Parts offers a full lineup of Pre-NAMUX harnesses engineered for trucks built before April 2005, including classic Peterbilt models (357, 377, 378, 379) and Kenworth (T600, T800, W900). These complete harnesses support pure analog, hardwired systems with dedicated ECM-to-dash wiring and no J1939 multiplexing—ideal for engine conversions or swaps involving Caterpillar (e.g., C12/C13, 3406E & C15), Cummins (e.g., Celect Plus, CM570/CM870), or Detroit Diesel (Series 60 DDEC3/4 & DDEC5) engines. Predominantly used in conversions to replace an existing engine or modernize older chassis, they provide OEM-style fitment and reliable connectivity for seamless integration without multiplexing complications. Perfect for mechanics and builders prioritizing straightforward installations and long-term durability in heavy-duty retrofits.