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i see guys in videos running sas with 36s on the rubicon and on moab. I have heard the toyota 8 inch rear end and front (straight axles) are as equivallant as a dana 44. I am currently running 33s and have room to go to 35s but when i look at a toyota housing with 35 or 36s and about 8 inches of lift it looks like a very small housing. What are your opinion on the strenght of a toyota axle, everything, axles ring and pinion. tell me if u guys have ever broke a rearend
 

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i run 35s with like 6inches of lift and i dont even worry about the axles, im actually locked front and rear as well. im running stock 4.10s at the time, but will have tcase gears.
 

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It's the birf's you need to worry about. Upgrade the birf's and 35's will do perfectly fine for most people. I ran 36's SX's locked in the rear, open in the front on stock birfs. Beat the everloving piss out of the rig and never broke one. Anything breaks though. If you know not to stay on the skinny in the rocks bumping your ass up a rock ledge 12"s at a time.....you'll do fine.
 

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with longfield front birfs toyota front axle is as strong as a stock dana "60" stock toyota rear is as strong as a ford 9".... they hold up great
 

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Yeah, the shafts and housings are plenty strong - the big issue with going with big tires is getting into deep gears. For good strength in the R&P, stay with 4.88's or taller - both the 5.29 and 5.71 only have 7 teeth on the pinion. Usually that means compromising street performance and having to do dual cases to have an acdeptable crawl ratio.
 

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weakyota91 said:
i see guys in videos running sas with 36s on the rubicon and on moab. I have heard the toyota 8 inch rear end and front (straight axles) are as equivallant as a dana 44. I am currently running 33s and have room to go to 35s but when i look at a toyota housing with 35 or 36s and about 8 inches of lift it looks like a very small housing. What are your opinion on the strenght of a toyota axle, everything, axles ring and pinion. tell me if u guys have ever broke a rearend
I'm running 37's. Locked front and rear, hydro assist, and a final crawl ratio of 244:1, I've broken a front HP 4.10 gear set, taken out a Bellfield and blew up a hub.

With the right parts, you can run 40's. There are people running 42's filled with water in buggies using Longfields birfields and they don't break, a handfull have... but everything breaks at some point.

You wil be fine with 35's. The ring gears are the weakest link after you beef everything else up, even then they can be pretty damn strong when set up deep and cryo'd. (trail rig)
 

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RedRunnertc said:
Yeah, the shafts and housings are plenty strong - the big issue with going with big tires is getting into deep gears. For good strength in the R&P, stay with 4.88's or taller - both the 5.29 and 5.71 only have 7 teeth on the pinion. Usually that means compromising street performance and having to do dual cases to have an acdeptable crawl ratio.
I'm running cryo'd yukons in the 5.29 favor, no issues. I did break a 4.10 set of HP gears, I believe its how things are setup and how you drive. I love my 5.29's and probably will not change unless I go fullwidth 1 tons.
 

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the people that have problems with 5.71s gears are the people who didnt have them installed correctly
 

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Totally agree jimbo - but the facts are that lower gears are always weaker than taller ones. Both 5.29 and 5.71 have 7 tooth pinions, 4.88 have 8 teeth and 4.56 and 4.11 have 9 teeth on the pinion. There is no scientific reason for a 5.71 to be significantly weaker than a 5.29, but you get a significant bump going to 4.88. If you are REALLY concerned about the strength, or wheel really hard, I think you're best served with 4.88's or higher.

Molly's truck has 5.71's and we just found out this afternoon that the R&P is stronger than the Birfs!
 

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RedRunnertc said:
There is no scientific reason for a 5.71 to be significantly weaker than a 5.29, but you get a significant bump going to 4.88.

Since all of these gears are 8" (or whatever) - They are basically the same size chunks of metal.
For simplicity, lets just look at the ring gears. THe lower the gear ratio, the more teeth on the ring gear- the more teeth on the ring gear means that the size of each tooth will be smaller than an higher ratio ring gear.
Smaller teeth ~ weaker

Its pretty noticeable when you have two ring gears side by side.
 

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TOYOTAPARTS said:
with longfield front birfs toyota front axle is as strong as a stock dana "60" stock toyota rear is as strong as a ford 9".... they hold up great
The only people making claims like this are people who've never run the 60 or the 9". Your comments are flatly FALSE.

Sean
 

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in the rear, i broke stock axles. r&p ,never had problems.
 

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BTW, please don't take the above post to be a negative comment about Toyota axles....far from it. I've run plenty of them and they are probably the strongest axle for the vehicle they were put in (in stock form in anything under a 1 ton).

The Toyota 8" (7.8" ring gear) rear axle will easily stand up to 38" tires with some common sense driving.

The front Toyota minitruck axle is also quite strong, especially when upgraded to longfields....but then you also have to start modding things like the ring and pinion and going to drive slugs or you just move your weak link.

Sean
 

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grillmasterp said:
Since all of these gears are 8" (or whatever) - They are basically the same size chunks of metal.
For simplicity, lets just look at the ring gears. THe lower the gear ratio, the more teeth on the ring gear- the more teeth on the ring gear means that the size of each tooth will be smaller than an higher ratio ring gear.
Smaller teeth ~ weaker

Its pretty noticeable when you have two ring gears side by side.
Actually, the teeth on a 5.71 ring gear are about the same, bigger in some dimensions than a 4.10:

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

as for the strength vs D60 or 9" comment, he was probably referring to this:
 

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There's a current thread on Pirate about Long's tests. The real conclusion is: the tests aren't really all that great. Too many variables to really call them anything more than a loose guideline.

What I do know is that I've seen plenty of setups working on the trail. There's a reason why most of the BTG boys went to 60s and ditched their Longfield equipped Toyota axles and it wasn't b/c 60s are cheap.

Sean
 

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RedRunnertc said:
Actually, the teeth on a 5.71 ring gear are about the same, bigger in some dimensions than a 4.10:
http://www.gearinstalls.com/410suck.htm
]
I was referring directly to the comparison of 5.29 & 5.71 since you mention both have a 7 tooth pinion gear.

I should have clarified if the tooth count on the pinion gear were equivalent.
In the case of the Tacoma 8.4 rear end- if you compare OEM 4.30,4.10,3.91, They all have a 10 tooth pinion gear IIRC.

When the tooth count of the pinion gear is not constant- the denominator is changed.
 

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I'll say they are fairly strong. I beat the crap out of my rig. I broke one rear on Backdoor at JV a few years ago on 35's.
Break at night

Fix in the morning.


I also blew up a bunch of stock birfs.


I went with Bellfields when I went to 37's and never looked back.
 

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Sean K. said:
The only people making claims like this are people who've never run the 60 or the 9". Your comments are flatly FALSE.

Sean
wrong!! I have 60's front and rear at the moment and love them...but the longfield 30 splines are very strong and w/37'' tire or less I have not ben able to break em,
 
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