Disclaimer: I personally have not done this route in entirety. However, I have been up Jett Canyon to the point where one must leave the trail and ascend the ridge. My knowledge of the upper route comes 2nd-hand from Nick N, Jose W and Joel B, and the GPS tracks from their trips (the GPS track on this page is an interpolation between their logs). Nick found the route to be scenic and pleasant. The Toiyabe Dome summit log indicates that people were able to drive 4x4s up Jett Canyon to 7400' in 2011. I've added this page because folks have found the "normal" Cove Ridge route to be very tough on the knees, especially during descent.
This is a very long route, especially if you aren't willing to scratch up the paint on your 4WD. If you park at the last open area on the 2WD road, the hike is 19 miles RT, over 6000'. If you drive a farther 2.4 miles (4WD, high-clearance) to the (fallen) National Forest sign, your RT trip will be about 14.2 miles with 5300' elevation gain -- but your 4WD will have taken a lot of hits from tough branches. (NOTE: Dean Molen reports there is now a Wilderness Boundary sign at 7000', so you can't legally drive the full 2.4 miles (as of Oct 2014).)
WARNING: the USGS maps show the road continuing all the way up Jett Canyon to the high pass; this route is described in Hart's Great Basin Book. In actuality, the road stops at the point indicated in the map below; past that point, the road is so terribly overgrown with willow and thorn bushes, that you MUST travel north onto the ridge as indicated, unless your skin is completely numb and like that of a rhinoceros.
From Las Vegas, take us 95 to Tonapah. At Tonapah, take US route 6 for 5.4 miles east to the intersection with state route 376. Take sr 376 an additional 47.1 miles north to the signed turnoff (left) for Jett Canyon (blue route on accompanying map). This signed Road is opposite Smoky Valley Road. This intersection is JETT376TRN in the waypoint list below.
Take Jett Canyon Road 4.85 miles WNW to the mouth of the canyon. This is about as far a 2WD, medium-clearance car will go. It is possible to drive 4WD, high-clearance vehicles another 2.4 miles to the Forest Service boundary, after which a berm is supposed to impede travel. This 2.4 mile section has much low brush that overhangs the road, and as of Aug 2006, was not suitable for any vehicle whose paint job was valued. ATVers, who apparently like Bud Light, may drive an additional 2.5 miles up the canyon, past the Forest Service boundary. Without an ATV, you must walk this next section.
The following account assumes you park at the end of the 2WD road.
From the end of the 2WD-navigable road (JETT-PARK1 in the waypoint list), follow the Jett Canyon road for ~4.8 miles, till the road is on the north side of the stream at ~7900' elevation (JET-XC-START in the waypoint list below). Before this point, there are many stream crossings. In 2002-2003 the stream was principally dry in late summer; in 2006, it was flowing well.
The next part of the hike is trailless, and is ~4.5 miles long (in addition to the 4.8 miles you just walked).
Leave the road, stay on the NE side of the stream, and begin to work NW then N up the ridge. You want to cross a wash to the N and get on the NEXT ridge to the N; so contour across the wash to the next ridge, as soon as convenient. Continue N on the 2nd ridge, then NNE, then N, then NW, eventually going over the 10522' point on topo map (Arc Dome 7.5' quad). Then continue N to the false peak marked 11144' on the topo, and cut ~ENE over another false summit, eventually gaining the true summit.
The most uncertain part of the trip is the stretch between Jett-tr2 and Jett-tr4. Near Jett-Tr3 you will have to traverse right (E) of the ridge, and follow on the E side of a precarious knife edge for a few hundred yards. (The alternative is to keep to the right fork of the valley at Jett-tr2, and head up a ridge to unnamed mountain. Unfortunately, you will lose about 600' descending west off that peak.)
Some waypoints (relative to WGS84):
38.710003, -117.118695, "376Jett-turn", "JETT376TRN", "376JETT-TURN", ff0000, 47
38.723470, -117.207182, "Jett-park1", "JETT-PARK1", "JETT-PARK1", ff0000, 47
38.735533, -117.242125, "Jett-paint-scratch", "JETT-PAINT", "JETT-PAINT-SCRATCH", ff0000, 47
38.755970, -117.267583, "Jett-XC-start", "JETTXC-STA", "JETT-XC-START", ff0000, 47
38.758060, -117.268140, "Jett-tr1", "JETT-TR1", "JETT-TR1", ff0000, 47
38.759363, -117.265386, "Jett-tr2", "JETT-TR2", "JETT-TR2", ff0000, 47
38.764464, -117.265128, "Jett-tr3", "JETT-TR3", "JETT-TR3", ff0000, 47
38.774368, -117.261021, "Jett-tr4", "JETT-TR4", "JETT-TR4", ff0000, 47
38.777704, -117.260572, "Jett-tr5", "JETT-TR5", "JETT-TR5", ff0000, 47
38.784334, -117.269738, "Jett-tr6", "JETT-TR6", "JETT-TR6", ff0000, 47
38.789648, -117.270979, "Jett-tr7", "JETT-TR7", "JETT-TR7", ff0000, 47
38.797177, -117.265203, "Jett-tr8", "JETT-TR8", "JETT-TR8", ff0000, 47
38.798847, -117.251552, "summit", "SUMMIT", "SUMMIT", ff0000, 47
Make sure you have plenty of water, after you leave Jett Creek. A set of dry socks may prove useful.