I was looking for a backroads route from Hollister to the San Joaquine Valley, across the Diablo Range. I took Hwy 25 to J1 to the town of Panoche. From Panoche, I continued east on Panoche Road.
Panoche Road is a good dirt road that can be used by any normal vehicle during dry weather. Most of this public road passes through private ranch land, so don't get off the road. Eventually, you will get to the Tumey Hills Public Use Area, where the cache is hidden.
Note: I left this cache while on a backroad/geocaching trip from San Jose to Houston. I will not be able to return regularly to check on it. Please log your comments on this website, so I can keep track of it.