Rating-wise, if you have a current model E450, you can "officially" load it to a scale weight of 45,500 pounds. Ford rates the combination at 22,000 pounds, so, again "officially" you could go to 7500 pounds towed. Equinox is a little over that, so again "on paper" you're good.
This is my experience. We run an E450 that's just a pinch under 14,000 with us and "stuff" for a trip. So 8,000 pounds left for towing. My Nissan Frontier weighs about the spec for your 'Nox. That's actual scale weight. I decided to rig our Corolla for towing and saved about 1,000 pounds.
So for me, and we haven't been West... 8,000 or not, I wouldn't want to tow more than the Frontier, the 'Nox.
But accept this Ford V10 Advice: Let it REV! It's built to do it and that's where it gets its job done. Try to lug your way along and you'll be disappointed.