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Current and future diesel engine oil categories have specifications that impose limits on SAPS (Sulfated Ash, Phosphorous and Sulfur) levels that help to minimize accumulation of ash in the DPF originating from oil consumption in the engine. Metallic species in the oil formulation, mostly from detergents and anti-wear additives, have a significant impact on ash behavior when subjected to high temperatures during active regeneration of the filter. Certain compounds in the oil, especially derivatives of ZDDP (Zinc Dialkyl Dithiophosphate), interact with filter substrate and sinter at temperatures that the DPF is exposed to during active regeneration. This phenomenon of sintering or ‘ash wetting’ leads to ash-bridges in the DPF that result in reduction of soot storage capacity, higher back-pressure and possibly reduced active surface area for catalytic conversion of engine-out emissions.