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So, I have a 2011 Express cargo AWD. We use my pickup to pull our TT but sometimes we like to bring our boat when we go camping as well. We used to use my wife's Grand Cherokee as our back up tow vehicle, but she has traded it in for a car so the van has to step up. The van has the factory towing package but I am concerned about the factory hitch's weight rating. It is only 400 TW and 4000 trailer weight. The tongue weight I am ok on, but the trailer weight I am not. Boat is around 6k with 350 on the tongue. (Yes, I know that sounds light on the tongue, but it's an aluminum trailer and their factory spec is 5% on the tongue and it tows perfectly...) Anyways, the receiver is also rated at 1000/10,000 using wd, which I am not. I'm wondering if the rating is more based on the vehicle or the hitch? Sometimes OEM hitches are rated on the vehicles limitations rather than the receiver's. Any thoughts on the Express? I can buy a Draw Tite 41921 that is rated much higher for $185, but don't want to waste my money if it's not a large improvement. Thoughts?