It appears that your Sequoia payload is slightly over 1300#. If the trailer were loaded to the 7500# max, your hitch weight might be as much as 825- 850#. That leaves 450# for fuel, occupants and other loading. Definitely an overload situation. But - It is best to start with the dry weight of the trailer and then add up what you think your total traveling weight will be, then add 11-12% of that as hitch weight. In that case, when you add up your weights, you might be way under your 1300# payload. Most likely, you will never come close to the maxing out the trailer weight. Don't worry about combined weight. You will max out payload first.