Something definitely doesn't look right with the trailer but I think your tow vehicle is part of the towing problem. I loved my Tundra and I will stand up against any of the haters on here, but frankly that is way too much trailer for a stock Tundra. Even more so for one with a 6" lift and big tires.
The dry weight of that tt, at nearly 8k, is about as much as a stock Tundra can handle comfortably. Forget about the fictionary tow rating. The dry tongue weight of 1060lbs exceeds the receiver rating before you even load it. Unfortunately, I see a new truck in your future.
I towed our current trailer at 7600lbs loaded with our '07 crewmax. It pulled fine but we were overloaded even though nowhere near the tow rating. I wouldn't want to go any heavier. You are WAY heavier.