UTV and 4 wheelers with high ground clearances are still able to get all the way to the trailhead. Saw a jeep last time I was out there. I did see a big rock stained with transmission oil though, so I guess it's not guaranteed.
it has been about 30 years since i drove in there and it was rough going then....but passable with 4wd...sure cuts alot of time off your hike if you can drive to the trailhead