Winter route advice- Calgary Alberta to Los Angles

[dpam]

We are planning a trip from Calgary Alberta to Los Angles the first week of December. We tow a 3150RL 5th wheel, therefore I'm wondering if anyone has a route they have taken that has minimal mountain driving. In the past we have taken Interstate 15 from the Canada/USA border to Las Vegas. I'm wondering if there is a better route for winter driving that avoids the mountains in Montana and Idaho?

Appreciate your input.

[hookman]

You could come along the Trans Canada to Kamloops then Highway 5 to Hope to the TC again to one of the exits to the border and then straight down I-5 to LA. I would take exit 73 to the border south of Aldergrove, B.C. which takes you down Meridian to I-5.