Search for my recent posting about the same issue on my 2008 Bravo III drives. The fix was to replace the end caps on both drives. My boat has always been on a lift since new, but over time, corrosion compromised the end cap's ability to maintain sufficient pressure to raise/lower the drive. The problem didn't happen suddenly, it was intermittent and got worse over a period of weeks. Eventually, they would not go down at all unless I had a buddy stand on the drive as I operated the switch at the helm. Other member's responses to my post said that it was a simple repair, but I'm not that mechanically inclined so I had it done, cost around $800.