: After initial installation, it is critical to perform a concentricity check. Cummins typically allows a maximum Total Indicator Runout (T.I.R.) of 0.008 inches JustAnswer Housing Options & Parts
Beyond the raw numbers, the torque sequence is the most critical factor during assembly. Technicians must follow a "star" or "criss-cross" pattern starting from the center and moving outward. This ensures the housing seats evenly against the engine block gasket or sealant. If the bolts are tightened in a circular pattern, the housing can cock slightly to one side, leading to a permanent misalignment of the crankshaft and the transmission input shaft. This misalignment often results in premature wear of the pilot bearing and rear main seal. Cummins Isx Flywheel Housing Torque Specs