We have a '13 350 Super Duty 4 x 4 Lariet. Still have the original tires. Am needing to think about replacement tires. 30% trailer tow: Gooseneck/Travel Trailer, 70% Highway. Want a smooth ride but a heavy duty tire. One that will last. Sometime in mud situations but 4/4 handles that. Thanks in advance, Trisha in La.