What is a Birfield???

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I have been looking into stronger birfields and I know what they look like and how they are important.............But what is the difference between the 30 spline and the 27 spline? I want to make sure that when I order the longfields before summer, I have the right ones.

Info on front axle: Solid disc brakes, WARN hubs, from an FJ40 with disc brakes.
 
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It's how big the input into the birfield is, stock 27 spline styles neck down while 30 splines don't and are stronger. If you're spending the money I'd say get 30 splines and chromo hub gears and never look back.
 

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I just got some spares E-bay $4.00 and haven't busted one since.

Just me and seemed more eco. considering I was spending on sag conversion at the same time.

note: I am learning as I go so I know very little
 
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So do I have to change anything from the third member or is it just the birfields themselves. The inner and the outer shafts. I.E. would 27 and 30 spline fit on my current front axle? Also, I want the strongest ones mainly because I am running stock and I don't want my friend, who has DANA 60s, to point and laugh when I bust my birfields.
 
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you didnt mention much about your truck .if its stock no locker and almost stock tires you probably dont need longfields.you also didnt mention what type of wheeling you do .only the extreme wheeling guys break the birfs ,some how that seems to be pretty common on here that they will break. i broke 1 in 39 years of beating the crap out of my truck.i have seen several dana 60s break also so maybey a little more resaerch before you spend lots of money .good luck
 
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So do I have to change anything from the third member or is it just the birfields themselves. The inner and the outer shafts. I.E. would 27 and 30 spline fit on my current front axle? Also, I want the strongest ones mainly because I am running stock and I don't want my friend, who has DANA 60s, to point and laugh when I bust my birfields.

No, both shafts are 30 spline at the differential so you are good to go either way however a 30 spline birf will not fit a 27 spline inner axle. I'd recommend longs only if you do quite a bit of tight rock crawling as a birfield usually only fails when bound up (ie full steering lock) and power is applied. I've personally seen a front mini truck axle live through two moab trips with stock shafts/birfs on 37's with careful driving, since I did the front axle rebuild I know for sure it's on stockies and not marfields/newfields/TG chromos.
 

Poser

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I'd recommend longs only if you do quite a bit of tight rock crawling as a birfield usually only fails when bound up (ie full steering lock) and power is applied. I've personally seen a front mini truck axle live through two moab trips with stock shafts/birfs on 37's with careful driving, since I did the front axle rebuild I know for sure it's on stockies and not marfields/newfields/TG chromos.



Sure....and I have broken those pieces of garbage with the starter motor....

:lol:







OP:

If you upgrade your axles, you will want to upgrade your lockouts as well. You will need to get factory lockouts and install the Chromo lockout gears in them.

:beer:
 
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as stated above, buy the Long 30 spline set (inners and outers) and be done with it.. they are extremely strong I have seen cruisers , on 42's wheeled hard with these, a stock birf is pretty easy to break if your locked in the front, like poser said get the chrome hub gears as well, as a broken hub gear can and will mess up the outer axle splines..
 
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Sure....and I have broken those pieces of garbage with the starter motor....

:lol:







OP:

If you upgrade your axles, you will want to upgrade your lockouts as well. You will need to get factory lockouts and install the Chromo lockout gears in them.

:beer:


I would do the BIRF eliminators and never look back. Poser could sell you a set. :D:cheers:
 

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What is a birf eliminator? Other than the obvious that it eliminates birfs.



Tim is just trying to be funny....


They were a product marketed by Warn 11+ years ago now, that they bailed on back in 2001, iirc. Others had them as well....was modified Dana 44 garbage...


:meh:



30 spline Longs/Chromo lockout gears for OEM lockouts, or Chromo drive flanges and don't look back.

:beer:
 
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Sure....and I have broken those pieces of garbage with the starter motor....

If you're spending the money I'd say get 30 splines and chromo hub gears and never look back.

Look at the third post and you see me say the same thing you said to do.

I didn't say they were strong or that I recommend it, merely that it's possible. I didn't say that the owner of the rig thinks the stock birfs would last but seeing how the group I wheel with are all in our early 20's after some discussion it was decided that longs could wait since other parts needed the attention more. I'm not trying to start a pissing match here just stating what I've seen :meh:


If anything here's pics from this year's trip (with exo cage, some new body panels, and rewelding of shady work by the PO) and last year's trip.

12306_382723631746_548186746_4288783_28990_n.jpg


4337_83076756746_548186746_2213910_3641129_n.jpg
 
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So, where can I get lockout gears??? Are they the Hub Gears that Longfield sells, they are Toyota Inner Hub Gear, they are Chromo, but I don't know the difference between the IFS and Solid Hub is. I have the stock WARN hubs that came with the front axle.
 
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in 2 years i went through 10 birfs all pass side. bought the TG 30 spline with hub gears and havent broken one in 3 runs. SBC,37 irok, and a toybox. are they stronger the longs not shure. but they were in my price range. now if you are open on 33's then use some 27 spline longs, TG, or marfields. what ever your pocket will allow.
 
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Tim is just trying to be funny....


They were a product marketed by Warn 11+ years ago now, that they bailed on back in 2001, iirc. Others had them as well....was modified Dana 44 garbage..

I have them on a truck I just bought. I was at Posers last Saturday and asked him if they are junk. I was then educated by Steve on what is good and how they break. He even had props. :D Then he showed me all the parts he has for them in stock at his shop. My plan is if they break to use the spares the truck came with, then I will help Steve purge his old inventory and create more room in his shop :cheers: and buy what he is recommending you do after that. When I type it out it sounds very expensive for me. :hmm:

Tim
 

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I have them on a truck I just bought. I was at Posers last Saturday and asked him if they are junk. I was then educated by Steve on what is good and how they break. He even had props. :D Then he showed me all the parts he has for them in stock at his shop. My plan is if they break to use the spares the truck came with, then I will help Steve purge his old inventory and create more room in his shop :cheers: and buy what he is recommending you do after that. When I type it out it sounds very expensive for me. :hmm:

Tim



It will be. :lol:



Save your money and go 30 spline Longs from the get go... :)



:beer:
 

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