[B_and_D]

We've driven to Seattle many times (but it's been a while) and Oregon many, many times. The worst grade that I can recall is around Ashland, OR. We towed the TM home from Salem when we bought it, and it wasn't that bad with our Chevy 1500 with the four of us in the truck. Sure, it slows you down some, but we were going a lot faster than everyone else with their big 5th wheels, etc. and putting very little strain on the engine. There are many lanes on that stretch of the highway (I think maybe 3 or 4) that allow travelers to sort themselves into various highway speeds from left to right. My DH always worries more about the downhill part and the brakes more than making it to the top.

There are some steep grades between Redding and the Oregon border, but I always remember that grade in Ashland as the worst (and they get snow there in the winter). From what I recall, between Grant's Pass and Seattle there aren't many steep grades.