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Truck 3rd v.s. FJ40 3rd 4 SAS,axle guru`s

Discussion in '40- & 55-Series Tech' started by Scottb, Mar 3, 2007.

  1. Scottb

    Scottb

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    I have a 1970 FJ40 front stock diff, I want to do a axle swap on my 1990 toy truck, is the third member in the cruiser stronger? they sure look bigger than my FJ80 front axle setting next to it.

    I want disc brakes, Longfields, hysteer, 4.88, ARB

    Do I need to turn the knuckles, I`m only doing 3-4" of lift.

    What is the fj40 caster to pinion, compared to the toy truck caster to pinion angle?
     
  2. bandy rooster

    bandy rooster

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    fj40 stock castor is like 1 degree or something..

    the differential in the fj40 is bigger then that of the 8" of the mini truck and fj80 axle, i think that the 80's had a reverse cut gear....


    you might need to turn the knuckles if your keeping it at stock wheel base, you can usually get away without that if you extend your wheel base a decent amount
     
  3. Scottb

    Scottb

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    This 1970 axle would be going into my 1990 excab truck, but I also have an FJ80 with the E-locker I might use, the fj80 is alittle wide, I think it is 5 inches wider than the rear axle in my truck now.
     
  4. JJS

    JJS

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    I would use the 80 front end. IIRC, the 80 front end has a smaller center section than the 40, which would mean the e-locker out of it wouldn't work. Put spacers on the rear axle.
     
  5. Tankota

    Tankota

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    Do the FJ80.

    The landcruiser pinion is usually a coarse spline. It is weaker than the fine spline ones which are either aftermarket or hard to find factory ones in the latter years. The fine spline one is the SAME size yoke splines as the toyota pickup ones. I use a toyota pickup yoke flange on my front diff. So all you basically get with the FJ40 front end is less ground clearance...that should get some people upset ;p
     
  6. Scottb

    Scottb

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    I going to use an fj60-62 front, they are 58"wide, and that matches my rear diff.
    Plus I can put the longfeilds in it, and have some custom chrome-moly inner axles made from front range offroad.
    I have a FJ80 with the E-Locker in ym garage complete, but I like the fj60 width better.
    WHO WANTS TO BUY AN FJ80 FRONT AXLE E-LOCKER COMPLETE???
     
  7. Tankota

    Tankota

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    Unlike cruisers your pickup spring perches are further apart...29" iirc. Whereas the FJ40s are about 27" maybe 27.5". The FJ60(62) are further apart than the 40s which led to problems when swapping the 60 front axle into a 40 due to the spring perch widths. You won't have this problem with the toyota pickup.:)