Building a van for Colorado
Start with winter. Under the traction law as updated in fall 2025, an all-wheel or four-wheel-drive vehicle needs winter, all-weather or mud-and-snow tires with 3/16 inch of tread on I-70 between Dotsero and Morrison from September 1 through May 31. A van that does not meet that needs chains or an approved alternative device for two or more drive tires, so plan where they live in the build.
Know what an all-wheel-drive van is not. On Medano Pass Primitive Road the Park Service requires a low-range transfer case and bans all-wheel-drive and two-wheel-drive vehicles past the Point of No Return. Length counts too: vehicles over 30 feet are restricted on the highway to the top of Mount Blue Sky. With towns from 5,280 to 10,152 feet, ask a builder how the heater, the water system and the batteries are expected to behave on a cold night at elevation.