I bought a used 2008 john deere 4105 with 60 hours. The 3-point lift arms will bleed down over night about 2 to 3" with rotary cutter attached. Also, while tractor is idling the lift arms will leak down an inch or so every 3 to 5 minutes and the hydraulics will quickly raise lift arms back up on its own. Just wanted to know if this is normal, Or should i have it checked out while under warranty.