Peak 4005 is a near drive-up summit a bit east of Mount Hood, accessed mostly on paved Forest Service roads. You should consider this summit in the Mount Hood 2m FM "dead zone" as we were not able to raise anyone on 146.52. Also, APRS and cell service were marginal or non-existent, so that spotting was very challenging.

This is a summit that you'll want a good GPS and map for, as the directions below should only be considered approximate. There could be other ways to get to this summit as there are a maze of roads in this area - these directions are reasonably straightforward. In the height of summer your car will get a heavy dose of dust, and in the wet, one of the roads may be slick with mud. Still, Peak 4005 is a drive-up summit that could be done in a passenger car - although for some of the potholes you may want a bit of ground clearance.

From Highway 26, take paved Oregon Skyline Road - NF-42 south past the snow park areas for 13 miles. Turn right onto dusty Peavine Road and travel for 6.5 miles. You'll reach a large quarry where you'll turn right and go under power lines. After about 1.25 miles, you'll be in the  AZ and about 1/6 mile from the summit. We found a small clearing on the summit side of the road to activate. 

From this side, the summit proper appears to be accessed only by bushwacking through heavy undergrowth. It could perhaps be more closely approached by a dirt road leading off to the left from this final road, but during our activation that road was closed due to forest fire suppression activities.    
For other summits in the area, you'll pass by the gate to the 5 mile RT hike to Clear Lake Butte off NF-42 and the turnoff for Peavine Mountain earlier on Peavine Road.