Cummins 3979372 Alternator Assembly

The Cummins 3979372 alternator is a 28V 70A charging unit designed for Cummins B, C, and L series diesel engines including 6BT5.9, 6C8.3, 6CT8.3, L8.9, L9, QSL8.9, ISC, and ISL. It features an internal electronic voltage regulator, clockwise rotation, and pad mounting with V-belt pulley. The unit weighs 8.2 kg and delivers stable electrical output for heavy-duty construction machinery and commercial truck applications. OEM cross-references include Cummins 4939018, 3415609, 3972529. Manufacturer part numbers include Prestolite JFZ2710F1, C3979372, G3979372. Aftermarket interchange numbers include SP122340, 860106517, SP135563, UD13917A. This alternator is widely used in equipment such as Liugong LG855H wheel loaders, XGMA958 loaders, XCMG excavators, and various heavy trucks powered by Cummins engines.