Hi,
Highway 120 is not for the faint of heart. If you have a lot of time driving the RV into the mountains, and don't mind taking highway 67 to 78 and into Julian, then you will have some sort of idea what highway 120 is 'like' but Highway 120 goes over a 9,600' pass, taller than Mt Palomar, and much steeper than the east side roadways.
I was in Lake Tahoe, and went south to Lee Vining, then stayed the night there. Took the RV and towed my Honda CRV up to the campground at the top of the pass on highway 120. Then took just the Honda to see Glacier Point, a place I had not seen in my many trips to Yosemite, because it was closed due to snow, or I was not able to visit in the summer. Glacier Point was wonderful, and you can see down into the many campgrounds of Yosemite Valley, as well as look straight across at things like Half Dome.
But the drive from Tioga Pass Camground down 120 into Yosemite and back is a BEAR. Lots of twists and turns, not something I would enjoy in a motorhome. Average speed is around 30 MPH due to all the slowing down for each turn.
Tioga Pass Campground had lots of pot holes in the roadways (I enjoy camping at Jawbone Canyon, where it is a sandy roadway, and I am 'OK ' with a primitive campground) due to all the damage that the freezing weather can do to the road that has cracks in it, that freezes, and heaves up, then looks like heck the next spring.
Once I returned to the motorhome and we decided to go back to Lee Vining, on our way back home, we decided to not tow into Lee Vining. My wife wanted to take the RV, and I drove the CRV - stopped to take wonderful pictures of our RV going down the hill a couple of miles ahead of me, from viewpoints that overlook the highway. It has many great places to pull off, let the brakes cool, and take in the views! Make sure that you are not in overdrive going down that mountain, and if required, pull down into second gear if you need to slow to 35 or so.
This is more a 'Advanced' roadway. This coming from someone who's parents owned a cabin on Mt Palomar, and enjoyed driving the mountains so much I took my sister up there in my motorhome for a visit, not the car. . .
Yes it can be done, but for those who do not like mountain routes, then taking 120 into Merced, then 99 north to Sacramento, then 50 into Lake Tahoe, and out 50 to Carson City, then take 395 south to Mono Lake is the way to go. It is miles further, and Lake Tahoe is enjoyable too.
AS for Sequoia NP, I did take my 1975 F-350 camper with 460" engine up the hill on the south east grade (I think from Three Rivers?), thought it nothing significant, until I took the 85 class C up there. It is really steep! I don't know if they will allow you to take a 36' motorhome up there, towing is out of the question. I did take my 30' Bounder - also a 460" engine, 1997, down that hill, and did fine. There is one point where the roadway splits, and goes around a tree that they did not want to cut it down. That tree is about 20 feet across, so you can tell how significantly long it would take to saw down such a large tree. Easier to go around it.
I would recommend taking the long route, and take highway 180 into and out of Sequoia NP. That said, I plan on taking a 23' van through Sequoia NP, taking highway 180 into the park and highway 198 south towards Three Rivers.
Last time I was there, I was in a 40' DP and got off highway 99 around Selma, then went north through the farmland, to catch highway 180, and go east up the mountain. Coming back home I stopped for some fresh peaches, got a whole case from a un-manned fruit stand for about $20.
The 'normal' way I would go into Yosemite is take highway 41. You want to be full of fuel before going into the mountains. Once you reach Coarsegold, the prices are expensive because they have to truck in the fuel. Get closer to teh valley, and it is more expensive. In the NP, there are no gas stations. IF you take highway 120 out, then there are none on the Tioga Pass either. Once in Lee Vining, there is some gas stations, but not reasonable ones. You have to go all the way south to Lone Pine, and then about 60 more miles to find gas shipped in from the fuel terminals near China Lake Naval Station.
As you enter Yosemite on highway 41, take a right at the entrance station. GO about 2 miles to the parking lot. Take the 1 mile trail to see the "Grizzley Giant" - a tree that is 33' across at the base. There is also a couple of tunnel trees in the area, one is large enough to ride a horse through it, with room to spare!
Highway 41 inside the park has a speed limit of 35 MPH with good reason, the roads twist like a pretzel. If you have not been through the tunnel yet, have your camera ready, and do this in the daytime. Be ready to turn left into the parking lot at the exit to the tunnel, or go straight if that parking lot is full (like it can be in the summer). Many pictures are taken from that location. Briadal Vail Falls is on the right, only about 1/2 mile away. Half Dome is to the far end of that valley, I guess about 7 miles away? There is a cliff on the left, and that blocks your view of Yosemite Falls (I think 1400' tall?)
If you can not fit into the parking lot outside the tunnel, don't worry, a shuttle bus will take you there and they stop about every 10 minutes, picking people up and dropping them off at the stops. My best recommendation to park inside the park, to the right (south, and towards the eastern end of the valley), and just before the turn off to Yosemite Falls.
How long do you have in Yosemite? There are day trips to Nevada Falls, and other places. If you have only 3 hours to visit, the rangers recommend that you go sit in the field and cry, then reconsider how much time you 'should' spend in a wonderful place like Yosemite. . . They spend months at a time, and still go back again the next summer!
I think that I forgot to mention seeing Grant Forest in Sequoia. Just north of there is a small roadway toward the "Chicago Stump". IT is a famous tree that was disassembled and carted off to the 1884 Worlds Fair in Chicago. Quite a feat to move a 18' diameter log 1,000+ miles in the 1880's, without the use of power equipment or trucks. All of the pieces had to fit into a lumber wagon, be driven down to Sanger, and put on flatbed rail cars for the trip back east. Then it was re-assembled, and pictures of that feat where to be sold for a small fortune, making the photographer rich beyond his wildest dreams.
Well they say that pictures must be believed, however it was claimed to be a hoax, and nobody could see that 18' diameter tree trunk and believe all that wood came from one tree. Even with all the pictures to 'prove it' was true! It was true, but nobody would get taken in by such a hoax, so the photographer went broke. .. It was easier to believe it was all a hoax than to think there are trees more than 10' across at that time, the largest tree east of the Mississippi was only about 4' across. . .
Nobody would believe the prospector that saw the 30' across Grizzley Giant either, but he convinced a group of other prospectors to follow him out into the woods in chase of a huge grizzley bear. This is how it got it's name. He lured them into the forest where the tree still is today!
Have fun on your travels!
Fred.
Money can't buy happiness but somehow it's more comfortable to cry in a
Porsche or Country Coach!
If there's a WILL, I want to be in it!
I havn't been everywhere, but it's on my list.
Kangen.com Alkaline waterEscapees.com