Difference between 40 & 60 knuckle balls (1 Viewer)

[abosely]

Is the differences between a 69'-78' FJ40 knuckle ball and a 79' & later 40 and FJ60 knuckle ball that the 60 & later 40 ball is relived or ground larger to fit the later larger Birf from the factory?

So grinding the 40 ball isn't weakening it, just making the opening the same size as the later 40 & 60 from the factory, correct?

Allen

 

[Fast Eddy]

Seems right. The outside, where the knuckle rotates is the same.

 

[DSRTRDR]

there is only a small area that needs grinding - pic is of a '72 front axle ground for the 60 series birf - from here https://forum.ih8mud.com/showpost.php?p=8751028&postcount=391

 

[inkpot]

IIRC, all Longfields are the larger size, so anyone that is considering them will need to enlarge the ID of the ball. I did my 76 in about 1/2 hour each side with a dremel. John

 

[Fast Eddy]

all Longfields are the larger size

They're also all the later style, so that follows nicely.