Wireless Networks are error-prone due to multiple physical changes including fading, noise, path loss and interferences. As a result, the channel efficiency can be severely degraded. In addition, in saturated multihop wireless networks, nodes with multiple hops away from the destination suffer additional throughput degradation signified by high collisions resulting in high packet loss. It has been shown that packets fragmentation and buffer size play an important role in improving performance. In this work, we propose a technique to dynamically estimate appropriate buffer size and fragmentation threshold for individual nodes across the network in reference of their locality from the gateway and on their traffic load. The results show that nodes far from the gateway incur significantly higher throughput. The technique also results in better fairness across all nodes. Furthermore, it enhances the total network throughput while lowering the end to end and MAC delays.