Ekki,
This may help.
The "Gunbarrel Highway" is an isolated desert track of 1400km from Wiluna to Yulara (via Jackie Junction and Docker River). In general, washaways, heavy corrugations, stone, sand and flood plains are all typical elements of the drive, but the track is graded occasionally by the Wiluna Shire Council from Wiluna through to 180km east of Carnegie. There are excellent bush camps, and many sites have bores with water.
You can pick up the Gunbarrel from either Wiluna in the west, or Giles (Warakurna Roadhouse) in the east and so it is usually done as an extension/beginning of a Canning Stock Route Trek Note, West McDonald Ranges Trek Note or The Tanami Track Trek Note.
At the western end of the trek, Wiluna is the launching point for both the Gunbarrel and the Canning Stock Route Trek Note. It is a town quite unlike any other in Australia. Other than the few people who service the passing 4WD explorers, the town is mostly aboriginal and there's just a few dusty buildings, a store, a pub and the camping ground, which is a far cry from the 1930s when this was a prospering gold mining town of 9000 people boasting the southern hemisphere's biggest mine.
At the eastern end of the trek, Giles is actually not a town at all but the homeplace of the Warakurna people and the location of a remote meteorological weather station, known as Giles. Visitors must stay at the Warakurna Roadhouse, where modern campground facilities, fuel and basic food supplies can be obtained as access into the aboriginal community is not allowed. Most people plan a visit to the weather station while they are here, which is little different to any other weather station around Australia. Visits are free, but you need to let them know in advance that you're coming, particularly if you want to observe the launch of a weather balloon.
Conditions vary greatly in this region, depending on how much rainfall has occurred in recent days and the volume of traffic and how long its been since the road was last graded. Please read these notes in conjunction with the detailed and updated WA Road Conditions Report that have been compiled with the assistance from the Wiluna Shire Council, the AN4WDRN and the assistance of ExplorOz users who report actual conditions to us.
In general, washaways, heavy corrugations, stone, sand and flood plains are all typical elements of the terrain. The major trouble spots are around Mingkili Claypan and between the Heather Highway turnoff and Jackie Junction (extreme washaways). The "abandoned section" from Jackie Junction to Giles is deeply rutted and in places quite sandy. During the peak travelling season (late June - Oct), many people make the journey across the Gunbarrel Highway so diversion tracks around major obstacles will be in place and even the abandoned section should not be overgrown unless you are the first group of the season after rains to push through the spinifex.
The Exploroz web site has alot of information on it which I use as one of many sources for planning a trip.
Cheers
Steve