SR5 limited slip in 4lo?

I previously owned a 2012 TRD Offroad, and when 4lo was engaged, all traction aids were disabled. If I got really stuck, it had the locking differential.

Now I am looking into a new SR5 (obviously no locking diff), and am curious what traction "aids" are operating when the truck is in 4lo? If there is no A-TRAC and no locking diff, and the normal traction control systems are disabled, is an SR5 in 4lo effectively running open differentials?

Thanks.

 

i believe it comes with an auto lsd for the rear where it uses the brakes to distribute power to both wheels. it isnt the greatest but it works. but i was curious bc when you take off the traction control on 2wd the auto lsd light comes on but not in 4wd low. but i was rock crawling the other day and it did feel like the lsd was working

 

I wonder if the light didn't come on because it doesn't operate in 4lo?