5.71 or 5.29 on 37's

[jrock]

I did a little searching and mostly found unfinished topics on 5.71s vs 5.29s. I would like to know peoples take on 5.71s on 37s and on road?

I know 5.29s are more popular but with the added weight of the 37s and the added size, it seams logical to step up to 5.71s. Are the 5.71s REALLY that weak? I can't get a great answer. The pinion looks wicked small but is that really all that bad?

I drive to every trail, hills and all. So good on road manures are a big plus.

[-Jake-]

I love my 5.29s with my 37s.  If you want 5.71s get them ZUK of www.gearinstalls.com says they're plenty strong and I'd take his expert opinion over anyones.   

[jrock]

Yeah, i read his stuff but even he doesn't say one way or the other. Just says they work.... I would like to have him set up my gears.

[-Jake-]

Yeah, i read his stuff but even he doesn't say one way or the other. Just says they work.... I would like to have him set up my gears.

I wonder what he charges to set em up.  I did both of mine and they're still holding up...  knock on wood

[-Jake-]

did you read this specific page?

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

[jrock]

Yup, just measurements. But he's comparing to a 4.10 set. I wish he had finished the review.

[kneedownnate]

ONLY way I'd run 5.71 is if zuk set them up 

[BLACKDOG]

I don't see a reason to run 5.71s with 37"s.  5.29s worked great with the 37"s

[Joey88RUNR]

Yup, just measurements. But he's comparing to a 4.10 set. I wish he had finished the review.

Did you buy those 37s?           I would run 5.71s  But not if i drove it daily.

[jrock]

Waiting on the seller.

I thought 5.71s do better on the road.

[wesley]

no dont go with the 5.71. ever. 5.29 is great for a 37, thats what i have. you would hate any lower gearing than that once you hit the highway. and the reason i say never go with 5.71 is because the teeth start to get so small on the ring and pinion that the longevity is comprimized and the the likelyhood of you blowing your diff on the trail is not in your favor. sorry bro, but yes, they are really that weak.

[jrock]

I'm running 4.30s with 33s right now and I assume the gearing to be about equal with 5.29s and 37s. On the highway it's great, even better if my engine ran at it's potential. But it's the extra weight of the tires I'm worried about.

If we get into the science of the gears then smaller teeth mean more contact between ring and pinon BUT... it's just that, smaller. I haven't found a good, complete, writeup on it yet.

[Jakesteads]

i run 410s and 37s... but i got a v6

[jrock]

i run 410s and 37s... but i got a v6

Your no help 

[86rustbucket]

elmo 83 on this board is running 5.71's  but i'm not 100 percent sure he's on 37's

ask him

he's that guy in the blue 3rd gen thats always up at bald with squirrel

[<MIKE>]

i Run 5.29 with my 35's and wish i had 37's for the road. the gearing is a bit low on the freeway for them. everywhere else is perfect. just with i could go faster  than 65 and thats at 3000rpm

[IronClad]

no dont go with the 5.71. ever. 5.29 is great for a 37, thats what i have. you would hate any lower gearing than that once you hit the highway. and the reason i say never go with 5.71 is because the teeth start to get so small on the ring and pinion that the longevity is comprimized and the the likelyhood of you blowing your diff on the trail is not in your favor. sorry bro, but yes, they are really that weak.

You should do a little reading.

[lucky7]

I've never heard anything good

[TacoRunner]

Jrock, dont bagin on ya, but the search feature is your freind on this one.

5.29 and 37"s bring your toyota truck back to stock ratio's and allow your speedo to be correct provided you started with 4.10"s. The speedo is calibrated from the factory so if you started with a 3.73 then you would need a 4.88 for you r 37"s.

With that out of the way, NEVER NEVER NEVER NEVER NEVER go with a 5.71 it doesn't matter who sets them up. The pinion gear on that gear selection is simple to small and weak to wheel consistantly and not break. That gear is about 30% weaker than the 5.29 due to is EXTREMLY small size. I believe the 5.29 has 3 teeth in contact with the ring gear at any given time, and the 5.71 only has two. Thats two small, little, pint sized pieces of steel hauling all 4500lbs of your butt.

[jrock]

haha, I like your stand point.



I think I have decided to run 5.29s. I now need to look at fixing up my engine and acquiring some bling Longs 

[BLACKDOG]

Jrock, dont bagin on ya, but the search feature is your freind on this one.

5.29 and 37"s bring your toyota truck back to stock ratio's and allow your speedo to be correct provided you started with 4.10"s. The speedo is calibrated from the factory so if you started with a 3.73 then you would need a 4.88 for you r 37"s.

With that out of the way, NEVER NEVER NEVER NEVER NEVER go with a 5.71 it doesn't matter who sets them up. The pinion gear on that gear selection is simple to small and weak to wheel consistantly and not break. That gear is about 30% weaker than the 5.29 due to is EXTREMLY small size. I believe the 5.29 has 3 teeth in contact with the ring gear at any given time, and the 5.71 only has two. Thats two small, little, pint sized pieces of steel hauling all 4500lbs of your butt.

I've seen guys in full size rigs romping on 5.71s all day long, with 42" tires and nothing happens.  Rock crawling, mud bogging, and snow wheeling.  If you read the link posted above, it gives a little insight into gear strength.  I've blown up two 5.29 gear sets, doing things that you wouldn't think would make them go pop.  Setup and quality of gears is huge, I think thats where a lot of people get their hang ups.

[jrock]

In the end it seams people are saying 5.71 ONLY if Zuk sets them up, when people are setting up their own 5.29s and having terrific luck. So, as I see it, if I have a reputable person set up 5.29s I'll be better off.

[TacoRunner]

I've seen guys in full size rigs romping on 5.71s all day long, with 42" tires and nothing happens.  Rock crawling, mud bogging, and snow wheeling.  If you read the link posted above, it gives a little insight into gear strength.  I've blown up two 5.29 gear sets, doing things that you wouldn't think would make them go pop.  Setup and quality of gears is huge, I think thats where a lot of people get their hang ups.

do you mean a Tundra, because american axles dont have a 5.71,   just want to clarify.

setting up your own or having some else do it, does not take away from the fact that you have less contact surface with the higher gear set. and seeing a guy or two romp around doesnt mean that much unless you see the that same guy all the time on the same gears. and even then mud and sand aren't as hard on parts as rocks are. Im not saying ZUK doesn't know how to set up gears, just that 5.71 have less contact surface.  

we need to also take into account what the truck is used for and what kind of other spec's the truck has.

[TacoRunner]

In the end it seams people are saying 5.71 ONLY if Zuk sets them up, when people are setting up their own 5.29s and having terrific luck. So, as I see it, if I have a reputable person set up 5.29s I'll be better off.

for the last 10 years Marlin has employed one man to set up all his gears, his name is Rocky. He has problably set up over 10,000 sets. Im sure ZUK's very good too, but do you really think it matters which one of these two does the work. Maybe it does and Im totally wrong, maybe ZUK does some cool tricks that Rocky doesn't. I dont think so, I've never spoken to ZUK. But I find it a little hard to believe that some how ZUK can make 5.71 as strong as 5.29.

[swapped89]

I have 37's and 5:29s, Yukon gears that were set up by a very reputable old timer. The gears are perfect for the tire size and I romp on them quite frequently. Its a good way to go.

[TacoRunner]

Toyota Bible

http://www.pirate4x4.com/forum/showthread.php?t=775780

[85_4RNR]

If you have 33s and 4.30 gears, a 4.82 R&P, if they made one, would have you at the same RPMs.
33/4.30=37/4.82

That said, I would say go with 5.29s because of the extra needed RPMs with bigger tires.


MATH IS COOL!!!  

[BLACKDOG]

do you mean a Tundra, because american axles dont have a 5.71,   just want to clarify.

setting up your own or having some else do it, does not take away from the fact that you have less contact surface with the higher gear set. and seeing a guy or two romp around doesnt mean that much unless you see the that same guy all the time on the same gears. and even then mud and sand aren't as hard on parts as rocks are. Im not saying ZUK doesn't know how to set up gears, just that 5.71 have less contact surface.  

we need to also take into account what the truck is used for and what kind of other spec's the truck has.

yeah, a tundra and a T100.  I've seen both trucks (and ridden in the T100) multiple times, wheeling in many different conditions, from rocks to sand to mud.  I'm not talking about a one time event.  Both trucks are heavily modified, one has a cage, one is running 42"s and the other is running 40"s.  Both locked f&r, one with a welded rear, detroit front, the other with air lockers. 

[jrock]

If you have 33s and 4.30 gears, a 4.82 R&P, if they made one, would have you at the same RPMs.
33/4.30=37/4.82

That said, I would say go with 5.29s because of the extra needed RPMs with bigger tires.


MATH IS COOL!!! 

  Someone else payed attention in math.

[muddywaters]

i bought my first gen with 5.71s already installed.  dont know how long they had been in there but judging by the setup of the truck(36s on 15x12s, 12" of lift, ladder bars) they have been street driven for a very long time.  i used them for 4 months, survived lots of highway and maybe 4 or 5 trail rides.  went to pull my buddies truck out of a hole and thats where i broke them(front and rear).  after pulling them apart i couldnt believe how small the head of the pinion actually was.  5.29s would be nice but i switched to 4.10s because that is the most common on the trail and i can get two complete 3rds at the junkyard for about the price of one master install kit.