PACCAR issued a recall on the 330 and T300 models

On certain vehicles, the Cummins engines were assembled using a pneumatic tool to install the boss plug, in which the air pressure was set high enough to create stresses in the cylinder block casting. These stresses could eventually create open cracks in the cylinder block or result in less than adequate clamping pressure around the plug. When the plug loses it's clamping pressure, it will loosen from the cavity, causing an oil leak. This leakage of oil, near the exhaust manifold and turbocharger has the potential to ignite and cause a fire in the engine compartment. Correction: Cummins will install a steel cup plug boss cap which is attached over the boss/cup plug location with industrial sealant.