If you are worried about the 5.71's being a bit weak due to pinion size, you can have em cryo'd by Bobby Long for like $40.
I had Precision 571 "4 cyl" gears cryo'd and Flexor(local hardcore here in Chandler area) has been beating them pretty good now for about a year. I commend Flex for having the balls to travel the lesser road and run 571 gears in a "4 cyl 3rd" to boot! The tooth fairy has not been there to visit him
....he has not broke his rear chrome-moly axles neither. 37" MTR's.
Here's the link of his 571 install...
http://www.gearinstalls.com/flexor1a.htmUPDATE:::: I just talked to Flexor
and got the latest scoop.... He's upgraded and been running 40" IROK's for some time now. He's not very stock in the horsepower department neither.....has a 4.3 Vortec in front of a TH350..................................I asked him about gear carnage on the trails that he's witnessed personally...Flex said he's seen a couple 410's....a couple 488's....and one 529 gearset go bye-bye.
here's his Blue buggy below with the 571 gears on a trail called TWISTED.
