Some RV dealers may let you hook one up to your truck and take a test drive with it, that really is the best way to get a feel as to how well it will handle. I just bought a 4300# camper and have a '11 taco with tow package, specs made me think it was well within reason. I am finding out now...
A vin# and a call to your local dealer will confirm weather or not you have a tow package. I have a 2011 4L non TRD w/factory tow package. It is rated for 6500 lb tow capacity.