OER Parts offers a wide selection of Battery Accessories for your 1978 GMC K15. OER Parts offers 1978 GMC K15 Battery Tender, 1978 GMC K15 Battery Managment System, 1978 GMC K15 Dual Battery System Controller Set, and 1978 GMC K15 Battery Relocation Set. Battery Mat Battery Topper Battery Terminal Protectors Battery Post Cleaning Brush Battery Terminal Puller