Recently, the use of mobile devices to run multimedia applications is becoming more popular. Such applications are known to be energy consuming. Since these devices are mostly battery powered with a limited battery life, energy saving strategies becomes vital for such systems operation. WiMAX systems utilize a standard sleep mode in order to reduce the mobile station (MS) power usage. It is also used to reduce the usage of base station (BS) air interface resources. IEEE 802.16e proposes three power saving classes (PSCs), depending on the type of the application(s) running on the device. However, when multiple applications that belong to different service types are operating simultaneously, the power consumption may increase due to overlapping among the used PSCs. In this work, a new mechanism is proposed to minimize power consumption of mobile WiMax devices. The proposed mechanism tries to eliminate the overlapping of PSCs by synchronizing the different PSCs. A simulation study is conducted and the simulation results indicate that the proposed mechanism can significantly reduce power consumption of MS; OPNET 14.5 modeler is the simulation tools that used in this work. However, this version of OPNET does not support sleep mode, but the sleep protocol is programed (in this work) using C Language inside the modeler, in order to show the effect of the proposed mechanism to enhance the power saving.