willing to climb, or rather, how steep do you want to avoid?
If you run as I and mrs_P suggest, the steepest grade you will encounter THE ENTIRE ROUTE is about 6% and that is only for about 3 - 4 miles at most. As a comparison, the grade descending out of the Eisenhower Tunnel West Bound on I70 is 7 to 8% and lasts for 7 miles. Ditto Vail Pass but about 8%. Vail Pass is, BTW, about the steepest and certainly one of the longest grades on the entire interstate system. (I realize no one has suggested you use I 70, I am just trying to illustrate how steep some grades get on the interstate system.)
From Bend headed East, you are on a plateau. The high desert. As you get closer to the Idaho line, you go through a range, but they aren't high peaks like the picture in post 16. In fact, US 20 follows a river through the range, so it is pretty tame.
Idaho across I 84 is no big deal at all. There are a couple grades, but nothing more than about 4% (just so you know, that means up 4 feet for every 100' forward) but most of it is just rolling hills. As 84 crosses into Utah heading South East, it crosses another range, though fairly low and the steepest through that stretch is maybe 5% but last for only 4 miles AT THE MOST.
Into Utah and it is flat running all the way till 84 hits 80. 84 joins I 15 at Tremonton, Utah, north of Brigham city. This is all flat road, but you are still 4300' up in the air. As 84 nears the North side of the Salt Lake City metro area, near Ogden, it cuts more Eastward and heads through the Wasatch Range. But this road, again follows a river, unlike I 80 which cuts up through a valley and has MUCH steeper grades getting from the valley floor in Salt Lake City up to the Park City area.
84 joins 80 near the Echo Reservoir, sort of out in the middle of nowhere, and turns more Eastward. It then climbs up onto the Western plateau of Wyoming, but this climb is about 20 miles and pretty gentle - about 4% max, most of it 2 - 3% up to the Wyoming State line at Evanston, WY. The most severe grades of the entire trip are outside Evanston and those are again, pretty tame compared to I 70 - maybe 5% max for about 4 miles at the most. Maybe one 5 miler if memory serves, but I never had a problem driving fully loaded tractor trailers through there in all seasons. The rest of the way across Wyoming is again, rolling hills for the most part. But as I mentioned, now you are actually crossing the Rocky Mountain range, it just doesn't look like it! You'll see high peaks to your right as you travel East, but nothing to worry about. But most of the southern tier of Wyoming is in excess of 6000' feet ALL THE WAY ACROSS so it is definitely subject to severe winter storms and it is not out of the question that Interstate 80 will close completely to traffic when the snow comes down too heavy. The longest, steepest grade on all of I 80 in Wyoming is just East of Laramie, WY, where you climb up and over the Laramie Range or Laramie Mountains. This grade is about 5 - 6 miles long and about 5 or 6%. Steep enough to get your attention going down, but a piece of cake going up. Then it is a gentle downhill all the way to Cheyenne.
From Cheyenne south on I 25 it is once again, rolling hills all the way to Colorado Springs.
It isn't that bad, it is going to be the quickest way and it will save you time and headaches. The other suggestions about going south to Klamath or north to Bend have some merit, but they both add miles and miles of unnecessary driving to your trip and really don't avoid any steeper grades than the route I suggest.
Trust me, I've been on all the roads mentioned in this thread many, MANY times, in both summer and winter.
I know what I'm talking about.
= new reply since forum marked as read
Being a natural-born smart-ass I have an affinity towards smart-ass remarks.
