This paper introduces a probabilistic methodology designed to estimate the corrosion wear in transverse bulkhead plating, a crucial structural element found in fuel oil tanks situated within the double bottoms of aging bulk carriers. By utilizing an extensive dataset of thickness measurements obtained during special surveys conducted at 5, 10, 15, 20, and 25 years of service, the study investigates the reduction in original thickness of transverse bulkhead panels across 25 bulk carriers. A linear multi-parameter distribution model is developed to depict corrosion wastage, with correlations established between the vessel's age and a presumed 14-year lifespan for the coating. The analysis encompasses 71 fuel oil tank hull structures and includes 1192 measurements of steel thickness reduction, expressed in millimeters. The formulation of the linear probabilistic model involved the consideration of multi-parameter distributions for two distinct watertight areas. The study treats the cumulative density function of the annual corrosion wastage within this linear model as a continuous random variable. The statistical, numerical, and graphical findings indicate that both the Inverse Gaussian and Johanson SB distributions are suitable for the probabilistic estimation of corrosion rates in the watertight bulkhead thickness plating of fuel oil tanks in bulk carriers.