My insight is stolen from SS Tim post #20 in the following thread. It does seem that they build some flexibility into the K series for offroad flexibility, but you really need to look at the payload ratings. I would be more concerned with offroad tires than a K frame. Check out Tims numbers, they are interesting and a good reference.
http://67-72chevytrucks.com/vboard/s...d.php?t=463016
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