The diff in the sixes blow way to easy.
The axles snap way to easy.
The car is as tough as nails, but the diff and axles are just to weak with a conversion to a ford 9 inch diff with billet axles you will never blow a diff again.
My HQ hasn't broken down yet apart from the rubbers coming loose in the gear box allowing the gear stick to jam (the Ute is 35 years old and has been put through just about every hard ship in the book).