From I-5 near Eugene, take highway 126 and head east towards Rainbow and McKenzie Bridge. However, a few miles before Rainbow you pass the small town of Blue River. From Blue River proceed east 2.5 miles on Hwy. 126, turn left onto USFS Rd. #15 for 3.5 miles north which is on the east side of the Blue River Lake (a reservoir). At the north end of the lake, start watching for FS road 1506 and turn right onto it and follow it east. At 7 miles, stay right on 1506. At 10.0 miles you come to FS road 350 on your left (north). If you turn left here you and follow it 6 miles you will be at the trailhead for Carpenter Mountain. For Lookout Mountain continue straight ahead on FS road 1506. Road 1506 gently turns from going east to heading south. You can see Lookout Mountain on your right or west as you continue up the road. At 15.2 miles from Hwy 126, look for a wide spot on this nice gravel road on the south side. This is at a little saddle at elevation 4340 ft and there is parking for a couple of cars here. This is the trailhead for Lookout Mountain, but it is not marked. If you get up to Frissel Point, you have gone too far.
The trail starts right next to the parking area and heads westward. The trail has been recently maintained and is in good condition. The trail gradually gains elevation and at about .7 mile from the trailhead there is a fork. Go right! The left fork goes all the way down to McKenzie Bridge. The right fork keeps gaining elevation and has a couple switchbacks as it makes its way up to a flattish open area on top of the south ridge leading to the highpoint of Lookout Mountain.
There is another fork in the trail as you enter this open area on the ridge. Go right again. The trail maintenance ended about here, but the trail was flagged with surveyor ribbon like the trail crews would be back to finish their work. Follow the overgrown and flagged trail north towards the highpoint. There are some downed trees to cross or go around, but the trail is fairly easy to follow. It ascends some rocky areas and then seems to peter out near the highpoint. Continue heading north up these low slope rocky areas until you reach the highpoint. There is nothing of significance to mark the highpoint, so I kept going until the ridge started to descend towards the forest. I then turned around and went back to the highest point that I had crossed. The highpoint appeared to be near the east side of the ridge amid short brushy trees interspersed with good sized rocks. I think rocks are smaller than boulders, so there is nothing technical here, just a little rock hopping until you think you have found the highest one.
The total hike covers about 4.0 miles, gains about 1,000 ft in elevation, and took me 2 hours.
The 10 essentials are always required. There is no water on the trail, so take all you need.