front axle u bolts square or round top near diff? (1 Viewer)

[calen]

hi, I searched a bunch and found no info on this, so hoping its just a known thing that I dont know. I bought an 85 front fj40 axle to swap into an 82 hj47 troopy to get front disc brakes. I was looking for 60 knuckles to swap, but found this whole axle thats actually for the car for cheaper then any knuckles I found. I figured rebuilding it would be way better. the axle that is on the cruiser currently has a square top u bolt that hugs the diff. The welded top perch thing that keeps the ubolt from sliding is different on the new axle as its a newer axle. it is kinda round shaped and its a little hard to say if the portion where the ubolt will actually contact the axle is round or square. this is a pic of it. round or square top bolt? im not crazy right? its hard to tell by looking at it?

 

[pb4ugo]

The fj40 axle takes round Ubolts. The one closest to the pumpkin is longer. I don't know anything about an hj47, are both of the axles the same width? Are the spring perches space the ssme?

 

[Chungas Revenge]

Round^^^.

 

[jim land]

My 84 is square and my 77 is round
Your look like the round type

 

[roadstr6]

Later trucks need the square U-bolts. My '78 takes round. My '82 takes square.

 

[calen]

Round^^^.

View attachment 3453038

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@Chungas Revenge Thank you! this quelled my mind perfectly p

 

[calen]

The fj40 axle takes round Ubolts. The one closest to the pumpkin is longer. I don't know anything about an hj47, are both of the axles the same width? Are the spring perches space the ssme?

longer? I dont think ive seen "longer bolts"? I thought they were all long, and that one not as much to cut off once installed no? as for the width, I never measured. was under the impression that all late model 40 axles are interchangeable?

 

[calen]

Later trucks need the square U-bolts. My '78 takes round. My '82 takes square.

weird, is that across the board? casue this is supposed to be an 85 axle, but its got the round top apparently? It has disc knuckles? guess it could be older? the axle has 27 splines on the outer end that goes into the birf and the birf has 30. that sound right?

 

[roadstr6]

weird, is that across the board? casue this is supposed to be an 85 axle, but its got the round top apparently? It has disc knuckles? guess it could be older? the axle has 27 splines on the outer end that goes into the birf and the birf has 30. that sound right?

Well, as far as I know, there were no 1985 FJ40 axles, at least not in North America. What you have is either from another truck or from an earlier year FJ40. The FJ40 stopped in North America in '84. Not sure about the spline count.

 

[calen]

Well, as far as I know, there were no 1985 FJ40 axles, at least not in North America. What you have is either from another truck or from an earlier year FJ40. The FJ40 stopped in North America in '84. Not sure about the spline count.

sure, but this is Canada, and people import all sorts of stuff, and its also a 40 series so there is hardly a one that isnt made of 5 others