Hey all, another silly question; Are 41 truck spindles the same as 41 passenger car spindles? Serious, I don't know...
Yes there is a difference there is a O1Y spindle ( heavy duty Pickup) that looks just like the car spindle but the inner bearing is different (larger) it takes the same king pin as the car.. If you check the upper king pin boss you should see an O1Y marking for identification. The truck spindle are easy to spot as they have a bigger king pin.
The passenger car King Pin diameter is 13/16" or 0.8125" As I understand the 1-tonners, those spindles have separate detachable steering arms. Noticably different structure. The service bulletins I have show the 1-tonner as also having the 13/16" diameter king pin. The trucks did however specify a 1" and also a 1.125" pins depending on year. 1941 truck I believe is the 1.125" spec.
I typed it so I don't know how you heard it but you heard wrong. The O1Y spindles look just like a car spindle but they have a bigger inner wheel bearing , the king pins are the same size as a car .812. If you have an 01Y spindle mixed in with a car spindle hub you cant get the hub to go on because the car inner bearing is to small to seat correctly. The 81T truck spindles are obvious as they take a bigger king pin and bigger bearings.