A method of manufacturing an overbased calcium sulfonate grease comprising a reduced amount of overbased calcium sulfonate, water and at least one non-aqueous converting agent, where at least a portion of the non-aqueous converting agent is added after one or more delay periods relative to the addition of the water. A delay period may involve the period of time it takes to adjust the temperature of the mixture, a period of time during which the mixture is held at a temperature or within a range of temperatures, and multiples and any combination thereof. These calcium sulfonate greases have improved thickener yield and high dropping points compared to greases of substantially similar composition made without a delay between the additions of water and a non-aqueous converting agent, particularly when a poor quality overbased calcium sulfonate is used.