In this work, a new strategy and algorithm for dimensioning transportation fleets for the delivery of consumerproducts from a distribution center (DC) to retailers is presented. The algorithm named CK, works on ahorizon in which a delivery forecast is deployed. Given a set of vehicles and the delivery orders forecast, avolumetric optimization routine determines the optimal length of a container having a standard width andheight. A set of parameters such as the desired customer service level, concentration level (i.e., expecteddeliveries per day), and expected growth rate, give the necessary flexibility for the decision making process.The CK algorithm simulates the behavior of costs for a finite number of test fleets and chooses the mostefficient. Efficiency is measured as the best assignment of volume to a delivery in a given transport. The CKapproach was implemented in a manufacturer and distributor of appliances in Santiago of Chile leading to adecrease of 25,8% of the annual spending in transportation services, an increase of 35% in utilization of theavailable capacity, and an increase from a historical performance of 95% in customer service level to a 99,93%.