We will be traveling from Cheyenne to Colter Bay on one of the legs of our vacation this summer. It will be late June when this happens. Mapquest routes us on I-80 then to 287 into the Tetons. Is this a good route? We will be pulling a 34 foot 5th wheel with a GMC diesel.
Route 287 to route 26 to Grand Teton is all good road. Route 26 climbs and descends over the Togwotee Pass but the grades are gradual. Great views of the Tetons on the west side of the pass. There may still be some snow in the trees at the top of the pass in late June.
Beautiful drive! If you need an overnighter stop in Lander and go see Sinks Canyon. We have stayed at Sleeping Bear RV Park and it was nice. That was several years ago.
X2 on these suggestions. Sinks Canyon State Park is only about 7 miles west of Lander. There is a campground there, but I'm not sure your 34ft 5er would fit. We spent a night at Sleeping Bear RV on our way home from the Tetons in 2010. It's on a hill overlooking the town with nice views of the Wind River mountains in the distance.
I would take I-80 to Rock Springs, then north to Pinedale and on to Jackson. There is virtually no pass to climb like Togwotee. The drive from Pinedale through Bonduant to Jackson along the Hoback River is some of the most scenic in the country.