Normally you'll bust ujoints before busting the d20, but it's not the stoutest xfer case out there. It's major appeal is it's 4lo gearing. If you don't get above 36" tires it'll probably hold up depending on how much of a lead foot you have. Chuck is now making a chromoly output shaft upgrade for the D20, if you're worried about breaking one. Personally I keep a spare output shaft while wheeling. If you do get into the more extreme wheeling most upgrade to a Atlas. I've been wheeling EB's for about 20 yrs and have yet to break a D20, but then I've been accused of being a wuss with the go pedal. I'm more a finesse over HP kind of wheeler