I get a washboard sound when towing and turning left or right from a stop.
I have a 1999 F-350 Super Duty 4X4 crew cab with 255K miles. When I tow my 5th wheel camper and make a left or right turn (Left is worse) I get a washboard sound. It has done this since 120K miles but is really getting bad. Transmission was rebuilt 25K ago.Where should I look? (Rear end, Universal joints) Please advise! Thanks