dont think i got any directions when i got the replacements but its a 3/4 x 16 socket head and that tq spec is freakin high! higher then any tq wrench i have here.
just checked the manual. it doesnt give the actual tq for that application but there is a tq/size chart. it doesnt show 3/4x16 but does have 3/4x10 at 155 ft/lbs for SAE 0-1-2 which is a low grade.
that 155 sounds familiar when i did mine but the low grade is probably why it broke (that and the adjustable sleeve which has some inner slack for more bolt stress)
I doubt it's torqued to the standard grade 5 specs, not when there are bearings involved, but who knows. For some reason I've got 65lbs in my head but I can't remember where I heard that! Is that the front axle maybe?