I can ask engineering if there is a number...but I've personally had 4 adults, probably 200lbs each in the front slide with no issue, I'm guessing that same number would work for the back as well. So 800 lbs. I seem to recall a while back 750 was thrown, but can't remember for what. Front slide has to pass a 5,000 lbs pull test for seat belts.
The question will always come with a follow up question. 800lbs doing what? Traveling down the road with the slide out? sleeping? Using it as mobile lab? X-ray machine?
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