A properly set up rear end w 5.71 is plenty strong. I read the artilcle, spoke with Zuk and swapped in a set of 5.71's and am very happy.
And no, this is not on some mall crawler. These are on a 84 Toyota class 7s dezert race truck. I am very hard on this truck yet have no concerns about running over 2' whoops, in 2nd or 3rd gear, with the built 22re (140hp) at 5200 rpm and turning 33" BFG Baja's (extremely heavy tire) on a V6 spool. They have run an entire race season with no issues. And I have friends that get 1 - 2 races out of a set of Ford 9" gears with a simular truck.
However, like the article says you must run a quality gear (ours are Precisoin V6 gears - not GG or a shimmed 4cyl gear). a solid pinion spacer and properly set up the rear diff. This includes torking the snot out of the carrier bearings.
The next time I do the rear end I will have the gears cryo's - to prevent the minute scuffing that does occur due to the hard racing use.
