I-90 is very well maintained and should be good. Watch the weather and make use of highway information,511 works great for this. The on I-90, first pass going east after you take I-84 to 395 to I90 is Fourth of July in ID. It is not bad but watch your speed as the curves are tight. The next one is between Kellogg Id and Haugan MT. It Is steep, long and the down hill winds in the mountains. again, watch your speed.
Haugan is home to 10,000Silver dollar bar and has a reasonable caf?, we usually stop for lunch there. They also have free parking out back with electric only. It is nothing fancy but is quiet and safe, did I mention Free!
The next pass is just east of Butte, about 7 miles up on a steep pull and a long winding descent, again watch your speed. Much of the down side is limited to 25mph for vehicles over 25K#. Shortly after Whitehall is another hill, it is not a pass per se but it might as well be as it is steep and slow with a long downhill but not very winding.
As you get to the bottom, there is a truck stop on the right and an excellent bakery and sandwich shop to the left, Wheat Montana.
The next and last pass is just east of Bozeman. The approach is through a winding canyon, not difficult but watch you speed - not difficult as you are going uphill most of the time. Just east of the canyon is a place to view bears, $$. Then there is a short steep uphill pull, a mile or so and then about 12 or so mostly downhill to Livingston. The Bozeman pass is just over 6000" and Livingston is about 4500".
That is the last pass but there are still some significant hills, one east of Columbus MT and a couple more east of Billings.
We have only been delayed once due to snow while traveling I-90 and have done it in all seasons. This was before the 511 implementation. Now Iwould only expect delays during a storm or immediately after before they got it cleaned up.
Stop and say hello as we should still be here as the Dr will not release me till sometime in May.
Have a good trip.
