The max tongue weight is simply 10% of the max trailer weight. For the factory tow package, the max tongue weight is 360 pounds. For a hitch installed without the factory tow package, the max trailer weight is 1500 pounds, therefore the 150 pound max tongue weight. Same hitch. The factory tow package does not include any changes to the suspension. You will be fine at below 360 pounds. Keep in mind the max payload for the van and body sag with the weight hanging off the back. You will want to manage both.