Advantages of a FF rear axel?

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As the title states I am wondering what the reasons for up grading a US 60 to a FF rear axle.

I will be building my FBJ60 up for expedition travel in the next few years and wondering if this was something that I should think about.

Thanks in advance,

Tim
 

2mbb

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the full floater is a stronger axle. It's built like the front where the wheel is supported by a spindle attached to the end of the axle housing and the axle it's self is only used to turn the wheel. If the axle breaks on a FF axle, the wheel stays on the spindle.

On the semi-floating axle, the wheel is bolted to the flange end of the axle and therefore, the axle supports the wheel. If the axle breaks, the wheel will probably fall off.

Do you really need a full floating axle? That's a different question that I can't answer.
 
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For my 62, I hope to eventually install a Toyota E-locker from an 80, so the FF is the first logical step. I will also need to have one axle machined for longer splines, or replaced with an appropriate axle. This plan should net me an all Toyota locker for the cost of the rear plus the locker, with a sellable SF housing and two spare thirds. (All 4.11's)

The additional strength is a by-product for my application, as my truck will rarely be at or near GVWR.
 
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The axle itself is not stronger, but the FF setup is better for carrying heavy loads because of the increased risk of axle breakage.

edit: wow, that doesn't sound the way I meant it. What I meant was, because the torsional load is greater on a heavily loaded vehicle, and therefore more likely to break an axle, it's prudent to have the safer FF axle.
 
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Pros:
- higher load capacity
- easier to service
- your wheel won't come off if you break an axle shaft
- optional cable lockers

Cons:
- $
- rare in the US

Edit: to clarify, the torsional strength of the axles shafts in a FF are the same a SF. However, with a SF axle payload is transfered to the axle shafts, and with a FF it is not. Therefore, the FF shafts see less load making the axle stronger as a whole.
 
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If the FF axle breaks, your wheel won't fall off. Their is also more expense involved with more bearings to worry about. Also, with larger than stock tires and lockers, the dowels and studs can shear off. Although I haven't had a problem yet.
 
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FF well worth it

Check out car-part.com - found a couple FJ80 FF E-locker axles for sale the shipping will be the real kick in the nads.

Good luck

I am looking for the same right now also:doh:
 

GLTHFJ60

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Due to the fact that the axles have no weight on them, you can pull the axles, and therefore the third without any jacking at all. At this point, the front and rear thirds are the exact same, so you can swap them if you break one of them.
 
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You asked for advantages, but I feel I should point out that the locking nut on a FF rear is not the same as on the front. The rear uses a different Stupid Service Tool (SST).
 
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I haven't researched this at all, but will the FJ80 rear FF fit an FJ60 ?? Some above posts imply that ...? Or am I mis-reading?

If you mean my post above, what I'm planning (contemplating) is a third member from an e-locked 80 installed in a slightly-modfied FF rear housing from a 60/62. This requires a different or machined axle on one side, and some grinding (usually) to clear the e-locking mechanism. I've not done this yet, so I'm probably missing something...hopefully someone will chime in so we can both learn...:D


Here we go...like THIS.
 
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Thanks, NJT ---

I'd like to find out because I'm looking for FF rear for my 60, then I'll install an ARB ...

Will a SF 3rd work in a FF? Or are the FF 3rd different?

Thanks,

S.
 
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Thanks for all the posts and information.

So I think for my application....a 3B that will be turbo'ed at some point, 33's, rear bumper with tire carrier and 2 cans, roof rack loaded, 2-3 people, plus gear: no super crazy rock climbing just typical expedition driving this is an unneeded up grade....

cool yes.....

am I better off putting the money towards other mods, I think so....

thanks again!

Tim


edit: thinking about this more the main reason I would do it would be the wheel not coming off thing if you break an axle. That could be key in the middle of no where. Is it worth it? Well that remains to be argued........
 
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Do you have an 80 series with the E-locker? My Tacoma and my 80 both have the E-lockers and I would rather have an ARB. They take a long time to engage, if they engage at all. Both rear ends are brand new in my trucks and still stick sometimes, if they engage at all. I am planning to install the 80 series rear axle I have in my garage into my 60 and I purposly bought the unlocked version so I could install an ARB which from my research has a stronger carrier, and the locking action happens almost instantly without much need for tire rotation. Yes it would cost more, and yes if installed incorrectly it could fail but the rigs I have been in that had ARBs when they pushed the button the diff would lock. Maybe I have bad luck and all 5 Toyota factory E-locking diffs that I have had experience with were sticking because I have heard people who swear by them. Also, if you plan on going bigger than 35s then you run the risk of twisting the splines on the axle shaft resulting in a fused shaft which is very hard to repair on the trail. I have not experienced this personally but I have read about it, and it is only an issue if you go bigger than 35s. Just my $0.02.


If you mean my post above, what I'm planning (contemplating) is a third member from an e-locked 80 installed in a slightly-modfied FF rear housing from a 60/62. This requires a different or machined axle on one side, and some grinding (usually) to clear the e-locking mechanism. I've not done this yet, so I'm probably missing something...hopefully someone will chime in so we can both learn...:D


Here we go...like THIS.
 
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Sort of off the topic, but...

Do you have an 80 series with the E-locker? <<<snip>>> Also, if you plan on going bigger than 35s then you run the risk of twisting the splines on the axle shaft resulting in a fused shaft which is very hard to repair on the trail. I have not experienced this personally but I have read about it, and it is only an issue if you go bigger than 35s. Just my $0.02.

Thanks for chiming in with this concern...No, I have not personally used the e-locker in any of my trucks in the past. I recognize the ARB as a great product, but at this time would like to try the e-locker. The typical problem areas with the ARB seem to be centered around the air supply to the third failing (usually install related) or the seal/o-ring in the differential leaking (not common, but still shows up once in a while). The e-locker may be slower engaging, but for my use I can deal with that. If it sticks, I can likely fix it without major drama. I'm also stuck on staying as Toyota-centric as I can...for no better reason than "I want to."

Regarding 35s, it is not likely in the foreseeable future that this truck will see taller than 31s, at least until I run through the first set of tires. This will likely take a few years. I am aware of the possibility of twisting the splines and sticking the axle in the e-locker, it is unlikely I would have to worry about it, though.

Last reason...The e-locked third can likely be resold for what I purchased it for. To resell an ARB I would take a significant loss. This would change of course if I were regearing right away, but I'm not.

Back on topic... (Sorry...:D)
 

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