Iíve read on here several times that the square drive at the bottom of the adjustable wrench first appeared for the 1926 model year.
Is the 1926-í27 wrench functionally interchangeable with the Model A wrench? Iím unclear as to whether the differential drain plugs are the same size or not.
The Model A is approx 3/8" square. The first Model A's used a slotted plug at the rear end and transmission drain before they went back to the square drive hole.
Is the late Model T plug also approximately 3/8-inch square? I don't have one on hand to measure.
Yes, it is.
Do any of the USA made wrenches have the T part number on them? Many of the varied makers' product I have found in Australia, have the part number as part of the forging.
Allan from down under.
Yes,many of them do.