I drove up in my Jeep with a friend in Aug 2016, the manual was nice going down. Just stick it in 2nd on the steep parts and relax. It went from sunny and around 60F to pouring, gale force winds, and 35F within 15-20 minutes after we got up there, they closed the road up and once the rain tapered off after a couple hours we gave some stranded hikers a ride down to the visitor center. No bumper sticker LOLI drove the family up years ago in my Honda Element which was a manual. A steep section of the road was under construction and we had to wait in traffic for the downhill cars to pass. Once it was our turn I kept stalling out, inching closer to the jeep behind us each time. Friggin' stressful.
I wasn't about to put the bumper sticker on my car but I would've earned it that day.