Take a look at the Bullet model230BHS that I recommended on the Keystone Bullet site to see all the specs. . 4370 lbs. I believe ypu are right with the 5000 lb limit on the Explorer, so that one would be well under your limit of 5000. I sell boats part time and have to look up towing limits all the time.. I think yours is 5000.. You said you have a towing pkg which gives you a class 3 hitch which is plenty. I do not think you will find an Ultralite any lighter than a Bullet. Remember.. you have to have room to live comfortably with 6 people under 1 roof.. The one I recommended will work and be under your tow limits. I recommend an Equalizer E2 weight distribution hitch as well! They make a big difference in the ability of your truck and TT to ride level and distribute the tongue weight to the trailer axles. Also great for non sway.. Also.. The Bullets have widespread axles which many others do not.. They make a BIG difference in smooth anti sway towing! Check it out.. Go look at one at your Keystone local dealer... You will love it!