FJ40 front axle question

[mdim]

So I've got a '71 FJ40 that was already converted to disc brakes years ago with an aftermarket kit. So still running the stock outer axle setup.

I'd love to get rid of the course spline outers and old Warn barrel hubs. Will a set of early mini truck outer axles and hubs bolt up by themselves? Or will they not work with the FJ40 knuckles? I can certainly swap the whole outer assembly if needed but then I need to find some (and I've already got discs that work great). The shafts themselves I can pickup new online for cheap and wanted to see if that plus a set of hubs alone would work.

Thanks

 

[pb4ugo]

You will have to adapt knuckles and birfs and outer components regardless if they are from a mini truck or FJ60/FJ40 disc brake front ends. The later disc knuckles have the provisions to bolt the caliper to the knuckle.

 

[mdim]

You will have to adapt knuckles and birfs and outer components regardless if they are from a mini truck or FJ60/FJ40 disc brake front ends. The later disc knuckles have the provisions to bolt the caliper to the knuckle.

What specifically is it about the fine spline outer axles that make them incompatible with the '71 FJ40 knuckles? Different length? Is the hub bolt pattern different?

 

[pb4ugo]

I see what your asking now. 1st I can only comment on US spec frt ends. Many yrs ago I broke a fine spline long birf(76 to 78). The only replacement i had was a coarse drum brake birf, and used it. All I had to do was use the course spline lockout. The drum birf shaft was shorter so I couldn't install the C clip, but could use a bolt and washer. I would guess the drum birf shaft is probably close to the same length as the 79 and later birf. I dont know if the bell is a different length. You might be able to use the fine spline birf and a short fine spline lockout. The 79 and later birfs bell is a bigger diameter than the 78 and earlier disc and drum versions, so folks grind the inside of the ball for clearance.

 

[mdim]

I see what your asking now. 1st I can only comment on US spec frt ends. Many yrs ago I broke a fine spline long birf(76 to 78). The only replacement i had was a coarse drum brake birf, and used it. All I had to do was use the course spline lockout. The drum birf shaft was shorter so I couldn't install the C clip, but could use a bolt and washer. I would guess the drum birf shaft is probably close to the same length as the 79 and later birf. I dont know if the bell is a different length. You might be able to use the fine spline birf and a short fine spline lockout. The 79 and later birfs bell is a bigger diameter than the 78 and earlier disc and drum versions, so folks grind the inside of the ball for clearance.

Gotcha, well if no one else chimes in with an experience I might just give it a try. In theory the 79-85 units should be really, really close in length. And you confirmed that the hub will bolt up. It's a mild trail rig, so a stock fine spline outer will make me happy from a strength perspective.

If I can swap just that it would be a cheap upgrade I think. Thanks for the input.

 

[pb4ugo]

If it works let us know.