We went Jeeping with 2018 Rubicon today. Drive about 5-15 mph, but no problem at all. Lots of ATVs also saw a Subaru made it up to Yankee Doodle Lake. Definitely need a 4 wheel drive for sure. One land unpaved rocky road but drivers on the trail was very polite. Took us 1.5 hr up and same time came down (including picnic and picture time).

Pass Yankee Doodle Lake and hike 1/4 mile to Jenny Lake. So beautiful and highly recommended!