Cummins Belt Tensioner, 3976831

Cummins B and C Series Belt Tensioner. Fits 4B 3.9, 4B 4.5, 6B 5.9, 6B 6.7, 6C 8.3, 6CT, 6CTA, ISB, QSB
Please Note: This tensioner has a grooved pulley. If your tensioner has a flat pulley and uses a non-gooved belt, please order item 3914086 instead. 
Cross Reference with Part Numbers: 3281583, 3934821, 3936213, 3945527, 3976831, 3976834, 3957434, J945849, 3945849, 87436755