Hwy 93 out of Missoula into Idaho

A little confusion in the route: You state you're 'getting off' at Challis and then 20 to Mountain Home. Does that mean you're driving from Challis on 93 to Arco then and west on 20/26/93 to Mountain Home. If so, your only pass will be Lost Trail on 93 at the Montana-Idaho state line. You'll have about 5 miles of 6% w/curves.

If you're not going to get off at Challis but instead, going to Stanley and 75 south to 20 west to Mountain Home. This route you'll have an additional pass - Galena Summit - just north of Sun Valley. If you go that way Galena Summit is 6% downhill for approx. 6 miles with curves.

Of the two routes the Stanley/Sun Valley way is most scenic because you'll view the Sawtooth Mountains at Stanley and a nice place to spend some time. In fact, from Salmon, ID to Stanley you'll be following the lovely river and there will be many opportunities to boondock or stay in national forest campgrounds or a few RV parks.

All the passes are done constantly by RVers as it's a destination route in summer. They are very doable. Just get in low gear before you even start heading down and you'll be just fine.

I agree on Torrey's. In fact, we drive up and stay there often enough, usually the Memoria Day holiday. Anne purchases cards of my artwork and sells them in her store. They were packed over the Eclipse last year.

There is a very peaceful RV park about 5 miles W. of Clayton toward Stanley, with a little store and some cabins. It is Torreys RV park and is on the river. FHUs. The only thing you will hear will be wolves howling at night. Great owners.

Pigfarmer, you won't have a problem. Semis take both these routes.

Few years back took 93 outta Salmon,Id to Missoula inna unsuspected snowstorm
27'Class A pulling Toad. DID NOT LIKE IT !!! JM2¢. YMMV

Sorry I didn't mention what we were driving. It's a 2015 Expedition diesel and towing a Jeep Liberty. Thanks for the replies. Sounds like a beautiful trip and pretty sure we will try it this time.

We've towed all over this state and into Montana and have driven those routes. You didn't mention what you're driving or towing, but if you have adequate power to go over any of the passes in Colorado, then Lost Trail and Galena Summit won't be a problem. Lost Trail is short and winding, good and wide enough. Galena Summit is wide enough too but the climb from the north is slow and gradual. Once you get to the summit, there is a rest stop. Shortly past the summit, on the way down there are some short and narrow turns, then a gradual ride all the way into Ketchum and Sun Valley. There's a nice wide rest area at the intersection of 75 and 20. Hwy 20 all the way is good with one very short downhill and winding section after you pass the turn off to Little Camas Reservoir. Again, if you have a setup with good power and control, then none of these are a problem, to be respected for sure, but the beauty can't be missed. If you happen to be passing through the Challis area close to stopping for the night, there's a very nice RV Park between Clayton and Stanley right on the highway, Torrey's Inn. They have a web site and full hookups right on the Salmon River. Easy in and easy out. Have fun.

There are two passes on that route - Lost Trail across the Continental Divide at the border between Montana and Idaho and Galena Summit between Stanley and Ketchum. It is a very scenic route with the Bitterroot Mountains in Montana and the Sawtooth Mountains in Idaho. The roads are in good shape and the grades are not extreme.

I have taken that route numerous times with my 5er and have never had any problems. You will really enjoy that drive.

A bit twisty at times, otherwise pretty benign as far as climbs and descents.

I have taken this route in our 36 foot MH, towing.
Nice road, nothing to steep, scenic along the river. Took it to Blackfoot.
Hal