Hello, I purchased my truck used about 6 weeks ago from a Dodge dealership In So Cal. It had 14,250 miles on it and it was sold as a Certified Used truck. I towed my travel trailer from So Cal to Tahoe up the 395/206 and it was great!. When I was backing into our camping spot on a slight uphill grade the trans would shudder/jerk a bit. It does not shudder without a load - on the flats. It works fine in forward, up grades and down. The original owners pulled a horse trailer with it and traded it in for a 2010 3500. I've read a thread about this and and I'm wondering if there is more info available. It now has 15.5K miles on it. That seems to be very low miles for a trans problem in my opinion. Is this a Certified Used Warranty Issue? The dealership tried to sell an extended warranty to me but I declined, maybe I should have bought one! Any ideas? and thanks.