This approach uses a logging road just off of the Troutdale road in Bald Mountain Township. Locate the AT crossing on the Troutdale road. The AT comes in on the west side of the road but leaves the east side of the road about .1 mile to the south. From the east side of the Troutdale road, Moxie Bald could be reached via the AT in 4.8 miles but also requires a ford of Baker Brook if you choose this option.
If you continue on the Troutdale road 1.8 miles south of the AT crossing (east side), you will find a well travelled logging road on the left. This is referred locally as the AT road. Turn left here and proceed around .8 mi and fork left. At 1.7 mi, bear right and continue to around 3.9 where the AT crosses. There are a few spaces for parking just before the trail crossing. The crossing is marked by signage, you just have to look for it. From this junction, the summit is about 1.7 mi if you take the summit bypass trail.
I was last in there in late May 2011, and a grader had just gone down the road the same day. The road was seeing traffic and was in good shape then. A car could easily make the trip, though it is unknown what it's current condition is.
PM me if you would like more detail.
Bill