This paper proposes a novel horizontal collaborative framework for grape transportation within a cooperative that supplies grapes for pisco production. Nowadays, each cooperative member collects and delivers grapes to previously assigned processing plants without coordinating with the other members. In order to evaluate the potential impact of shared transport resources, we model collaboration among farmers as a cooperative game with transferable cost, where a mixed integer programming formulation that models transport activities is repeatedly solved for computing the characteristic function. Although the grand coalition is theoretically better than any other coalition structure, our approach limits the number of farmers per coalition to assess incremental collaboration's benefits. By conducting a case study involving sixty farmers, we show that a collaborative approach leads to a 13.4% reduction in the cooperative's transportation costs. However, we observe that the benefits of collaboration show diminishing returns. Particularly, we show that a coalition structure with a maximum number of three players per coalition captures almost 94% of the maximum potential savings.