I have a 2008 Avalanche and had to replace the lift as it was jammed. This seems to be a common problem on 2008-2014 GM 1500 series trucks. The lift has an additional locking mechanism that jams over time. I'm an average DIYer so after watching some YouTube videos I gave it a try. The cleaning process took about 60 minutes from start to cleaning. Out of all the videos I've watched, I recommend the guy from Canada.
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