I had a jack on my Stablelift fail after almost 3 years. I don't think that is too bad for as heavy a camper as I have. But this is not to complain, just share info. First if you didn't recieve a emergency handle with the lift you should have. I didn't, they are sending me one now. Second the jacks are very easy to work on. I contacted Mont at Stablelift and he told me how to check it out to see if it was in the "Gear Head" or the "Jack Screw". Easy check, Three allen scews to lossen and the head comes off, Switch it with a known working one, if jack works then the gear head is bad, if not it is either no power or the Screw. Mine was the power head. Took the cover off the head, it had stripped a gear. This one was a pheonlic (spelling) type material. Called Mont, the new replacements are metal ($35.00) Ordered three to change them all. Just letting everyone know that these Jacks are easy to work on.