In a HC 4x4 the road is drivable all the way to Mt Lindeman trailhead. The big washout at 7.5km (from end of pavement) is fairly mellow, at least for a 2-door Jeep Wrangler on 35" AT tires (aired down to 10psi). Probably not for Subarus and Rav4's, but anything Wrangler-like should have no issues going through it. After that there are a few smaller washouts, but if you can make this one, you will make the other ones too. The "avalanche of trees" a bit further up has a bypass around it. Some sections of the road are starting to get grown in, if you care about your paint.

We stopped at 6.0km, where a rocky water bar was too much for our Rav4.
At 7.3km, the road is impassable where a creek washout covered the road with a wall of dirt, large rocks, and tree trunks.
At 8.0km is another impasse where tree trunks are piled 2m high across the road, probably from avalanche activity.
Both of these blockages would be impassable for any road vehicle. It did appear that some kind of ATV had climbed over and around them.
To clarify locations, my distances are measured from the point where Centre Creek Road turns off from the main Chilliwack Lake Rd. (There can be some confusion, because there are old km marker signs posted along the upper Center Rd that measure from the point where the road turns upstream along Centre Creek, which actually 4.3 km from the Chilliwack Rd)
To be clear as possible, the current major impasse is at 7.3km from the Chillwack Rd, at elevation 763m, which is 3km from the permanent road closure that serves as the Lindemann trailhead.

New washout just before 7.5km

Drove to the 6km mark where it becomes overgrown. Some recent work has been done on the road, the washout/downed tree reported in January has been cleared. The water bars are also less deep than I remember last year. I think you could get a moderate clearance vehicle through all of them. Great season to access some of the beautiful east faces on Illusions, Nesakwatch, and Rexford!

Drivable in Subaru Crosstreck to the marked washout. We think this or similar is the minimum you need for this road.