Own a 2011 Forest River Berkshire 390QS motor coach. Bought it about 6 months ago. The large dining room slide always opened slower that the large slide opposite it. I believe the dining room slide woks on electric motor & the quicker slide opposite it works on hydraulics. The slower slide now will only open half way then stops. It will retract just fine, though. What is the issue, all other slides (3) on the coach work fine. Leaving in 8 days for a 2 week trip; what can be done?