Lubricating oil compositions having a sulfated ash content of no more than 1.0 mass %, which contain a major amount of oil of lubricating viscosity, a minor amount of calcium salicylate detergent, an amount of a magnesium-based detergent providing at least 200 ppm of magnesium, and a basic, low molecular weight, nitrogen-containing dispersant, which compositions provide improved top ring wear protection in internal combustion engines.