No problem. We take our dually crew and 39' fiver thru there yearly. The pull north of Ashton isn't bad and most of the pull has a slow lane. But I will say this, from Ashton to West Yellowstone is a very recreational area. There is another very slight pull from the east end of Island Park to the Idaho-Montana state line at Targhee Pass. Please obey the descending speed limit signs and also keep an eye out for wildlife crossing the roadway. After dark all bets are off! Beautiful area and enjoy.