Without going to 60's, or portals... (1 Viewer)

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Eskimo

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What's the next "best" thing?

Been tossing around the idea of a FJ-80 front with Bobby's 4340 birfs, and some pig inners, full hydro. In the back, a 31 or 35 spline 9", housing trussed, nodular 3rd, etc...from a EB (Or, a FJ-80 rear perhaps? I can deal with the slight offset) This would give me exactly the width I want, with off-the-rack rims (78-80" wide)

I'm not sure why... wanting to go against the grain, trying to think outside the box, wanting to keep the weight down at a reasonable cost, or just being "cheap" (i.e. pennywise, dollar foolish)?

On a light cruiser like mine(~3500lbs), I would think this combo would hold up well with a ~39" tire... Heck the 80 guys at well over 6k lbs are holding up OK!

Though this wouldn't get installed for a while, some of the parts are coming available right now at the right price, so I feel I should make a choice now.

I know, it's no 60... There, I said it... But does it NEED to be?
 
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Kinda off-topic, but why the need to truss the housing on a 9"? Will the housing flex enough to cause a problem?
 
my next rear axle will likely be a 35 spline 9" setup....big bearing, shaved housing, detroit, etc. I would not bother with one from an EB, but source some of the stronger/later versions to modify. (Sunray has some good experience with these...)

Full floater cruiser rear is still 30-spline at the diff and is only stronger from a LOAD capacity, not from a shaft strength standpoint (tho, much easier to get chromo's made)

Considering the 80 front is still 30-spline at the pumpkin, and it runs the smaller/weaker minitruck sized gearsets, I'm not convinced it's a worthwhile upgrade to a built Cruiser front axle....again, until you increase spline count and shaft size, any upgrades are minimal.
 
I just say why? You spend all of this money on modifying it to fit, money on the shafts and birfs and you have an axle that will be hard pressed to hold up.

Also, 3500# is a hard target to hit for a trail rig.
 
The info that led me down this path was this from the 60 bible..

Standard Dana axles (1040 steel, induction hardened)

30 sp 1.31" 6,044.1 ft/lbs
35 sp 1.50" 8,966.2 ft/lbs.

Aftermarket 4340 steel, thru hardened

30sp 1.31" 9,923.5 ft/lbs
35 sp 1.5" 14,721 ft/lbs

Stock 35 spline inners would be enough for *me* on a 60 front... and if 4340 30 spline shafts are ~10% stronger than that, it outta work...

Am I way off on my thinking of this?

The 8" ring gear is weighing in heavily against the 80 front though... how much does the reverse cut config help though? I've still got a coarse spline pinion up front on my 40... certainly a fine spline 8" reverse cut is comparible to a coarse spline FJ-40 pinion, isn't it? yes? no? no f'n way? (And yeah, I realize that in reverse, it's driving on the coast side of the gears...)

The cost seems to be lower than building a 60 is also HEAVILY driving this... $600 on birfs, $300 on shafts, and the front axle is ready to take the same setup as any other axle (That is to say, steering setup and links will be similarly priced no matter what... no cutting, hub-swapping, gearing, brake conversions, new wheels, etc required).. Brakes are done. width is correct. Caster is good (I wouldn't need to cut & turn the housing). I have wheels & tires that will work. even the drive flanges are taken care of.

Are the guys that are wheeling on the 80 axles just not abusing them? I thought Slee broke a stock inner, and that took some real doing...

PLEASE keep in mind, I'm not disputing anything said here... Just trying to fully understand, and enjoying the information exchange... :beer:
 
Woodman's right, Id stay away from the EB housing, they are the weakest ever made, and in the rear you should have plenty of room for a wide (26") housing. IMO a stock 9 housing isn't really up to the task (thats why we dont use them) because of the thin wall tube, many have good luck with them, but if I'm gona sell it, it has to be able to with stand my style of wheeling, and needless to say, I don't trust stock tubes. My suggestion if your not going to buy a complete custom, is start with a good housing built by some one who knows what they are doing, spend $ on the 3rd (good race stuff, no polar bear food) go 35 spline, and forget about it. If you need any 9" info I know a guy.
LG
 
Thats the kicker, all the truck housings are good housings but they are usually too wide, that sucks, but reason #100000 we dont use stock stuff. Some of the car rears are a good width but you have to yank the bearing pockets to get to 35 spline.
LG
 
So why not narrow a truck housing???

BB 9" ends are like $65 a pair...
And you need custom shafts anyway...



THis seems easier than I am reading about...
 
Since you've got Ford 9" on the brain, why not a pair of HI-9's? For the front, get Sunray to build up a 1550. I've seen a Prorock 60 center in a 1550, why not a HI-9? For the rear, source a late 70's Lincoln Versailles housing with the disk brakes already on it & some big Ford bearing ends to swap in if you wanna save a few pennies. That is if the center section holes would lineup with the HI-9's. Are you wanting to build this yourself? If I were considering another axle upgrade, I'd steer clear of birfields again, IMO.
 
LC_Hamma said:
Since you've got Ford 9" on the brain, why not a pair of HI-9's? For the front, get Sunray to build up a 1550. I've seen a Prorock 60 center in a 1550, why not a HI-9?

whoooaaaa. Budget, remember? ;) The only good things I heard about the Hi9 was from the manufacturer... :D

Hamma nailed it - I'm wanting to do as much of this myself as possible.
 
How did we get on rear axles? I thought you were asking about fronts.....

Anyway, build the Cruiser stuff until it can't hang. With your new weight you may be surprised at how well it will hold.

Step up to a D60 from there ala Mace buiild. Strong and cheap.
 
I had 80 series axles under the truck stock that is why I used them. If I had to build again, not sure if would use it. I have broken my fair share of parts and currently run Longs' + Poly front axles, Moser rears. Have never broken the ring and pinions, but just about every axle and birfield. Current setup did good last run at Penrose, but then the crawler box helped a lot. So far so good. I am going to go to 42's, however if I break again, they are coming out and something else is going in.

Using the 80 axle in anyting else is not so easy. Hi steer arms are not easy to come by for the axle.

As for the rear, I would not use the 80 electric locker again. The splines on the axle twist between the dog gear and the diff and then you can not get the axle shaft out. I would go 80 non-locker with detroit or spool if you want the 80 rear axle.

We have friends that run the front in built Taco's with 40's and also in built 4Runner with 42's. Both have experienced their share of birf and axle breaking.
 
Eskimo said:
The only good things I heard about the Hi9 was from the manufacturer... :D

I've heard lots of good from fat trail rigs around here :confused:

Doesn't matter much to me, I'm probably always gonna have junk yard axles.
 
You could do what W did at Over The Hill 4x4 and take a FJ80 front end put rock well outers with an e-locker converted to air. He runs 42's and hasn't broken it yet :D
 
I never understood tha mod...
 
Mace said:
I never understood tha mod...


Me three, esplain please.......


Guessing the toyota center secontion is going to save many pound and increase strength on the outers.
 

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