What trailer wt could I tow safely?

payload is going to limit you. check your door sticker to get payload, subtract weight of everything in the truck (gear and people) and any aftermarket accessories added, then subtract weight of your hitch (usually 90 ish lbs). whatever is left is approximately your available tongue weight which should be around 13 percent of trailer weight (I say work with 15 for safety factor)

example

1800 lbs payload
- 500 lbs passangers
-200 lbs gear
- 90 lbs hitch
=1010 lbs
1010/.15=6733.3 lbs max loaded trailer weight.

this is a good place to start