As AlexB indicates all those roads are fantastic. Might want to consider doing all 4. As you are starting on 120 at Lee Vining (eastern side of Sierra's), taking the 120 accross. Travel 49 north to Sonora then go east on 108 back toward 395. Then travel north on 395 and take 4 west toward Arnold and Angel's Camp. Then travel north on 49 and take 88 accross Kit Carson pass.
You won't regret covering all 4 roads. Plus the temps are perfect at this time of year at those elevation (high 60's to low 70's).
120 is obviously most traveled (because of Yosemite). 88 is 2nd most, followed by 108 and finally 4. But I think 4 is the best. At the top it is single lane and winding - but very little traffic and fun to ride.
All roads are paved and very scenic. It's the best of the Sierra's.
108 over Sonora Pass is a bucket list run. Alpine roller coaster above the tree line going over the pass. If you have camping gear your in for a real treat and its all free. You'll need a fire permit from the ranger station of fire dept.
We lived in Atwater CA from 1983 - 1987 and again from 1993 - 1994. I've ridden all 4 passes many times, and loved every mile of all of them. Watch out for the gravel in all corners the higher elevations you go. Take plenty of time, take a camera, and stop often for some of the prettiest pics you'll ever treasure.
:agree:with all of the above. 88 is good. Going east just before you get to Nevada in Markleeville is the intersection with 89. You'll have the choice to continue on 88 or go south on 89 to Hwy 4. I like 4 with all the twistys. Be careful on the sharp corners of 120. Lots of sand and gravel due to trailers cutting the corner. If you're planning to head south on 395 you can also go south at Markleeville on Hwy 4 and follow it south then east to 395 to just south of Lake Topaz. Have a great ride!