Were you driving in 4wd auto? If so that would indicate why your front diffs kept blowing up on you. These trucks have 12 bolt ifs front diffs from aam that are one of the best front ends you can get, period, but if you are driving in 4wd auto and the front tires go from spinning to hooking up, youll easily destroy that front diff, especially at freeway speeds. Other than that, they are disengaged if driving in 2wd so no way they could randomly blow up in 2wd unless physics are being defied here?