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This is the ipod I have (80 GB) iPod classic Navigation: Click Wheel Capacity: 80 and 160 GB Model number and date introduced: A1238: 2007-09 The iPod classic is a hard drive-based iPod featuring a large, widescreen color display, a Click Wheel, and the capability of displaying photos and videos. It uses USB for syncing. The last three characters of the serial number will be one of these: Y5N, YMU, YMV, or YMX I am planning to buy a 160 GB drive - will I be able to replace the 80GB original drive with this one?

as long as the drive was manufactured specifically for the iPod video you are planning to switch it with, then yes. However, you cant buy a 160 for a 3rd gen, and attach it to a 5th gen. These repairs are very difficult to do without damaging the housing, so be sure you are prepared for some cosmetic damage to the framework.