If your not into really hardcore wheeling then i would say dual cases are probably more then you need, the lowrange in your stock t-case should be plenty for a hunting truck. I say this because I run some pretty wild stuff sometimes and I dont have duals, the 5.29's get me low enough for now (for me anyways). I have also noticed there there are some design flaws regarding the inputshaft on the crawl boxes that seems to make them more or less unsuitable for long term DD use.
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