anybody ever do it? any issues with the 3rd fitting in the stock housing?

 

I think the main problem with anything over 5.29's is that the teeth on the ring gear end up too small and break easily.

 

i doint think thats the problem, ive never heard that anyways. im just worried about it clearing the stock housing. actuall i did read that the pinion is small like you said, thanks

 

Should fit fine, at most you may need to hit the notches in the axle housing flange with a grinder to gen clearance for the ring gear theeth (I usually find this is needed w/ 5.29s). According to Zuk, 5.71s are fine:
- http://www.gearinstalls.com/410suck.htm

 

thanks 4 crawler. i heard its a myth that 5.71's are weaker. theres alot of misinformation on the web, but this looks like it makes sense.

http://www.gearinstalls.com/410suck.htm

 

X2

The 5.71 gear "myth" seems to be just that! Throw them in.

 

they fut but it comes close. a properly set up 5.71 is just as strong as anything

 

10-4 im still debating on the 5.29 or 5.71 i really want to get a high pinion 3rd for the front but i havent seen 5.71's for them. (i havent looked real hard either) if i get a high pinion 3rd can i use the carrier from my regular 3rd or do i need a new carrier too? i was planning to get the housing , gears and an aussie lunchbox locker and take it to the gear shop. from what ive noticed the only difference in the high pinion gears is the pinions are a little different. the ring gear looks to be similar. do you guys know if the regular install kits and stuff will work on the high pinion??

 

My 5.71's fit fine. They say the the Pinion gear is too small and only has 4 teeth on the ring gear at any given time while the 5.29's have 5 and 4.88 have six. Whatever. If they brake then I will put 5.29's back on but I am going to leave them there until they do. I mean the 4runner weighs between 2700 and 3000 pounds and has 106 horses. Even with 35's I Just can't see that I could over torque the pinion. My brother in law has a full size blazer on 44's with a 350 and 1 ton axles. I don't think he could get away with 5.71's, too much weight and torque. I guess it is all relative

 

According to this write up http://home.4x4wire.com/erik/diffs/ the gears that are available for for the Hi Pinion are 4.88 and 5.29. They came stock with 4.10

 

I've read Zuk's reasons for the 5.71's being strong and I agree with parts, but the bottom line is there is a difference in the surface of teeth engaged. Since there is more pressure on arguably fewer teeth, the theory is that the pinion is weaker... that theory does make sense, and isn't covered in Zuk's write-up. Can this be reduced with a proper setup? Yes. Eliminated? I don't know.