Web caching has been recognized as an important way to address three main problems in the Internet: network congestion, transmission cost and availability of web servers. As traffic increases, cache clustering becomes a natural way to increase scalability. This paper proposes an efficient scheme for increasing the cache hit-ratio in a loosely-coupled cluster. In such a cluster, each proxy is able to serve every request independently of the other proxies. In order to increase the performance, the proxies may share cacheable content using some inter-cache communication protocol. The main contribution of the proposed scheme is an algorithm that increases the performance (hit-ratio) of any cache-pruning algorithm in such a cluster.