Hi all, we are planning to travel on highway 12 through Idaho on our way from Oregon to Montana. We are in a 1 ton Silverado gas motor hauling a 33 ft crossroads travel trailer, which is pushing the boundaries of what the truck should be hauling. We are looking for info regarding concerns we should have on any of the downhill sections and whether anyone has had any major issues such smoking the brakes. Any input as to whether this is a stupid thing to attempt, or if anyone has made the trip and has suggestions etc. is much appreciated.

Know how to downshift. We went up that way and it's a fantastic scenic route. It follows the river for much of it and kayakers and bicyclists are all around. At least during normal times. We had no problems with the truck and while there are grades I don't recall any extreme climbs or drops. IIRC the road climbs steadily for the whole first section.

Agesilaus, thank you for your reply

Downshift BEFORE you start gaining SPEEDUse brakes sparelySTAB them and quickly scrub off speed (reduce by 10 mph) then GET OFF THE BRAKESRepeat as needed to maintain downhill speedUphill.....grear down and use higher RPMStay in right lane and don't expect ahny spped records

Take a look a the Mountain Directory - West. It will give you information about steep grades and curves for your route.

We've taken that route many times usually coming home from Yellowstone working our way back down through Oregon and back to So. Calif in our class A.95% after you pass Lewiston is meandering road about 45 mph. The only steeper section is going up the Lolo Pass as you enter Montana but it is not bad at all. It is a very pleasant drive and we think well worth it. Toward the Montana end at the start of the pass is a campground called Powell. It has electricity and is on the river. If you time it right and want to camp there you'd hit no traffic going up the pass the next morning.

Lewiston to Lolo pass highway 12 road questions

paulj
Explorer II
Apr 13, 2020
In L&C days, the easiest route (by foot/horse back) was along the ridge top, not the valley beside the river. Steeper grades, but not as brushy.
ken56
Explorer
Apr 13, 2020
12 follows the Lewis and Clark expidition route fairly closely. There is a visitor center at Lolo pass that is worth a stop in. It is a beautiful drive. There is a law that you must pull over and let other vehicles pass if yiu are 'holding up traffic. There are pullouts on the road but I found them to be lacking in notice and always wound up passing them. I was not going to jamb on my brakes just to be able to pull into one, and I was only doing 45 most of the time.
mittshel
Explorer
Apr 12, 2020
Another vote for Powell CG. We had no problems on that road. 40' FW. A beautiful drive. Take your time and enjoy. Betsy.
hornet28
Explorer
Apr 12, 2020
As someone already mentioned, downshift when descending rather than using brakes when possible. We just did that complete route in late June. It's beautiful area one not to hurry through. We found a nice and certainly inexpensive campground. It's the Pink House Recreation area 38 miles east of Lewiston right on the Clearwater River. It's $9 a night w/full hookups for seniors and a 15 day maximum stay.

https://thedyrt.com/camping/idaho/pink-house-recreation-site
paulj
Explorer II
Apr 11, 2020
The route has been used for oversize oil field loads - Lewiston is the nearest sea port to Montana and Alberta.
Lynnmor
Explorer
Apr 11, 2020
You'll be fine, there is only one serious grade as mentioned above. The road is never ending curves but only a few of them will test that long trailer. Beautiful drive, don't miss it.
romore
Explorer II
Apr 10, 2020
That is a beautiful trip, just don't push and you will be fine. When do you plan to go? It's a little early to attempt Lolol Pass with an rv.
Camper8251
Explorer
Apr 10, 2020
If this trip is in the near future.....

Sorry not to be a negative nelly but Do you plan on self quarantining for two weeks when you arrive here?

Montana is under a stay at home order and all travelers are required to self quarantine.......

Directive
MDKMDK
Explorer
Apr 10, 2020
Install Google Earth Pro, and do a "Get directions" from start to finish. When the route is displayed on the map/earth, right click it, and select "Show Elevation Profile". It will show the entire route's ups/downs with grade max and min slopes in either direction.
TUCQUALA
Explorer
Apr 10, 2020
Going west to east, you'll have an easier downhill after Lolo Pass than the other way. Using the lower gears and brakes cautiously, and not letting your speed get out of line, you'll be ok. The pull uphill on the west side (last 3 or so miles) is do'able, but you won't be setting any speed records!!! It is curvy (!!) here and there (!!), but a good beautiful 2 lane road. Depending on when you are going, and day of the week, be aware that the road is loved by motorcyclists and the spandex mafia!! Watch the curves for them at all times!!!