The new bottle clearly says GL-5 on it, See below. I can't comment specifically on GL-4 vs. GL-5 for the later model vehicles, only that my similar AWD Torsen/4x4 T-case from my older Toyota specs GL-5 75W90 for it. If you really want GL-4, I'd buy an aftermarket fluid (like the one shown above for $10/bottle).
If Toyota has discontinued the straight 75W gear oil and is now only selling multi-viscosity GL-5 gear oil now, IMO it would seemingly invalidate GL-4 being the required "spec" for that transfer case.
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