Good idea to check what you have. They might be P-rated tires, which are common on SUVs, even larger ones like your's.
If so, and if its time to replace, consider LT tires. They usually offer more load carrying capacity than a P-rated tire (although that is not always true. There are some P tires that match LT-C load ratings).
I personally like LT - Cs for my setup. They offer a bunch of positives but in general are less squishy and provide a better towing experience without being too harsh when not towing. Load range Cs have a max load pressure of 50lbs.
Load range D and E are available, too, depending on your size tire. But you might not be able to fully utilize those because of limitations with many SUV wheels - The D and E max load pressure of 65 and 80lbs, respectively, could be higher than your rims are spec'd for.
DW, 3 Kids and our Goldens
2012 Shamrock 233S
2008 Toyota Sequoia 5.7L 4WD