half ton 6, 3/4 ton & 1 ton 8.. the dually s used 5 lug fronts and 10 lug rears and the only dually's were the BIG trucks
ford ran a big 5 pattern then about 1958? 1960? switched to a big 6 on the f500-f700
the f800 with the air brakes got the modern semi truck 10 lug pattern
I had a 1958 f350 and it had 17.5 tube type non split rims and either 5 or 6 lug i cannot recall.
It also had a big ol timken rear axle with 6.88 gears and top speed of 35 mph
the 6 lug ford went to is the same as jeep kaiser and studebaker and maybe dodge? international?
I've never seen a chevy big dually with anything other then the lighter duty 5/10 lugs or the heavy duty semi truck pattern