8" diff - 70 Series front Axle Q's (1 Viewer)

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EWheeler

4 Cruisers, No Garage !
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Some recent posts by @Will Van has me curious about 7x series front axles with 8" diff. I have searched the forum, and am not seeing what I am looking for.

Here are the questions I am after:

1. Can FJ40/FJ60 knuckles/hubs & birfields be used on the 8" diff 7x series front axles? (i read that the knuckles ARE different, but it wasn't exactly clear how they were different)
2. Spring perch center to center width on the 8" diff 7x series front axle?
3. WMS width for the 8" diff 7x series front axle?
4. Length of long & short side inner axle shafts?

I am planning to swap an ARB locked high-pinion 8" front diff & housing into one of my FJ40's. Not exactly wanting to spend the money on a custom housing at this time, so my initial plan is to use an 8" mini truck front housing. On a mini-truck housing, the long side inner axle is the same length as an FJ60 where the short side is about 2.5" or so shorter than the FJ40 inner axle. I would lengthen the short side of the housing which would net me about 1.25" of housing & WMS width gain per side from my current FJ40 front axle, which will help with current tire to leaf spring clearance issues. I can use a normal FJ40 short side inner axle with this modification.

The high pinion will be nice, but really I'm using it because I already have the ARB locked diff. The 8" diff housing will help me by increasing ground clearance marginally, but the smaller diff diameter will also allow me to gain some chassis "lift" as I can get the SUA spring perches much closer to the OD of the diff housing than the factory 9.5" diff housing allows. I am curious if a 7x series 8" diff housing may be a shortcut for me and eliminate any custom fabrication like lengthening a housing.

Thanks for input.
 
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