The trail head is accessible by any vehicle, but at 30 ft, you may not have room to park in the parking lot, or to turn around, depending on how many others are parked there. Park in a camping spot and hike to the trailhead. There currently seems to be nails on the dirt road from the highway. I got 2 punctures - one in the truck and one in the trailer - while camping there last month.

Yes, accessible without 4WD. 30ft can turn around in parking lot IF not busy. There are several campsites close to the trailhead if busy. Roads are dirt and gravel and a bit washboarded once turning from 95.

Yes! The trailhead for Palm Canyon is accessible without 4WD. The parking lot is not very big though (and often busy) so you may need to leave your RV in a camping spot and walk a bit.

We pulled our 25ft to up the dirt road. The first little bit of the road was soft but no problem getting through it. Plenty of parking at the trailhead during the week. So have no problem but if you decide not to drive to the trailhead you just park in a spot for camping and walk.