From NorcalTTORA
http://www.norcalttora.com/trails/deer_valley.phpThe Deer Valley Trail
Rating: 6 
The Deer Valley Trail connects highway 88 and highway 4. This scenic trail has two water crossings which can be moderately deep in the spring and early summer. Some of the more challenging sections include large boulders and off-camber spots adjacent to steep hillsides.
Requirements: To participate in TTORA Deer Valley runs, you will need to have 4WD. Rock sliders and lockers are recommended to prevent damage, although this trail can be navigated by a stock truck and some careful spotting.
Directions: From highway 88 exit on Blue Lakes Road. Blue Lakes Road is about 2.5 miles west of the highway 88/highway 89 intersection and about 67 miles east of the highway 88/highway 49 intersection. Follow Blue Lakes road about 12 miles. You will come to an information display for the Blue Lakes campgrounds. Take a left and follow the shore of the lake to the trailhead.
Gas Up: If you are heading up highway 88 get gas in Jackson. If you are heading up highway 4 stop for gas in Arnold.
GPS Coordinates:
Highway 88 trailhead: N38°36.480 W119°55.523
Highway 4 trailhead: N38°32.341 W119°53.803
The highway 88 side starts down a rocky trail next to the river. It then opens up into a very scenic meadow and sometimes deep water crossing. There are many tight spots on this trail. Careful driving is required to avoid leaving paint on rocks and run-ins with trees. After reaching the summit, the trail heading down to highway 4 has some off-camber spots next to a steep drop-off. This trail (and all Sierra trails) change from year to year due to weather and erosion. This particular spot gets a little more tippy every year. Once down the hill toward the highway 4 trailhead, the last obstacle is a large boulder and a rock pile that have claimed many a quarter panel or door. There are several moderately steep and boulder strewn sections on this trail. Rock sliders are helpful in many spots.
