The ACL Trac 3 main bearing set for D155/D179 engines is a 0.25 oversized main bearing kit intended for engine rebuilds requiring an oversize main bearing. Trac 3 bearings are supplied as a matched set for the specified journal dimension and serve as replacement mains when a 0.25 oversize is called for during machining or overhaul procedures.
ACL International Trac 3 D155/D179 - 0.25 Oversized Main Bearing Set