I finally got the opportunity to tow my dad’s fishing boat, and overall not too shabby. He has a 22 foot Alumaweld Intruder that I’m estimating is about 4.5k when loaded up with gear and fuel. My truck averaged 16.5 MPG. Going over Stevens Pass, it got down to 55 MPH on the steep sections, but was able to hold that speed unless I had to show down due to curves or slow trucks. It wouldn’t rise above 50 on the steeps if that occurred. The fishing was a bit light, but we still have some headed for the BBQ and smoker.