Another bit of advice - if you go UP in 3rd gear (for example), go DOWN in the same gear. Let the transmission/exhaust brake do the work. We live in Pagosa Springs, CO, and travel over Wolf Creek Pass (US160) frequently, which is much steeper than I-70, without problems. Enjoy the trip!
And, welcome to iRV2!
Joe and Debbie, Emma the Aussie Cattle Dog who adopted us
2012 Discovery 36J, Blue Ox and Air Force One, 2010 GMC Acadia Toad
USAF (Ret) WDØM http://wd0m.com