Design and manufacturing of spur idler gears of gearbox by means of traditional methods, involves too many times of trial and error and consequently spending too much time and money. Utilizing new technologies such as CAD/CAM will increase productivity and flexibility of the process (PDP). In this paper, different parameters and characteristics of the parametric design process of the spure idler gear using CAD/CAM have been discussed and a method for parametric design has been presented. Using this method, design of parts of the same group can be done within the shortest time and by inputing parameters for any part, a typical design can be achieved. Due to the comlex contours and high accuracy requirements of the gear theeth, gear manufacturing is highly specialized, demanding much machining time and therefore is costly. Material wastage is also another problem in these process. In recent years, there has been increased interest in the production of gears by precision forging. Precision forging enables gear teeth to be manufactured to net or near-net tolerances. Resulting in significant savings in raw material and production time compared with conventional cutting methods. In contrast, precision gear forging is associated with problems related to die design, preform volume and geometry, tooth dimensional accuracy, load and energy prediction, ejection problem and finally tool life. These are also reviewed in this paper. Finally, designed dies for manufacturing a typical spur idler gear, analysed by “Super Forge” software.