I have a TiVo HD with lifetime service and symptoms of a failed hard drive (stuttering, temporary freezing, pixelation immediately before and after freezes and "Fail 7" result on kickstart 54 tests). I have a My DVR Expander but it checks out fine in the drive tests. I haven't opened it yet to see if the power supply has any damaged capacitors, but I'm assuming it's OK for now. Question: I want to spend a minimum amount of money to repair the TiVo HD's hard drive. A local seller has a used one for $40 (including power cord, remote, and network adapter) which they say works without any problems. If I buy the used TiVo HD, could I just put its hard drive in my TiVo HD without reformatting hassles? I assume it would require unpairing the Expander and that I'd lose all the existing recorded content. I also realize this has some risk because I don't know how long the used drive would last, but a new drive is more than I want to pay at this point. While I have the box open I would also check the power supply and replace caps as necessary. (Or if I have bad caps and I'm feeling lazy, maybe just put the ps from the used unit I buy into mine.) Are there any other pitfalls I should beware of? I STF and suspect this has been covered before but I didn't find it.