MTFCA Forum

I am looking to put innards into my tapered axle 6 rivet rear housings. Will innards out of a 1915 and up rear axle fit into the 6 rivet?

I replaced the straight axles in my 6 rivet rear without issue. Of course I had to change hubs as well. It was many years ago but, as I recall, I used the rest of the innards from the original axle and replaced the thrust washers with brass and steel. Set up was difficult but it all worked.

Russ, that’s great. thanks for the answer and your help.

Depends upon the year of the six rivet. And I don't offhand know when they changed. Earliest rear ends had Babbitt inner bearings and smooth the full length axles. Those rear housings are quite difficult to upgrade to roller bearings inside, but I have heard of it being done. I have never been directly involved in that project myself.

My '10 is a mid-March car. It did not have babbitt inner bearings but it did have straight, not tapered, axles. I just swapped axles using the gears off the old ones so the rest of the components were from the original 6 rivet rear.

As I say, I am not an expert on these early early cars. I know that the the first rear housing did not have rivets near the differential. They were a single extruded piece of steel. The extrusion process left the thickness of the metal uneven, and the extrudable steel tends to be soft yet work hardens resulting in uneven strength and flexibility. The result was that the one-piece extrusions were too weak and fragile for the wight of the car and road stresses. That style did not last long (although I think much of 1909 model year). Ford soon switched to the riveted two piece stamping/extrusion which was considerably stronger and more reliable. I am not sure if the switch to roller bearings inside by the differential happened at the same time? or before or after the change to the riveted centers. It is also important to note that the first thousand or two cars had poured in place Babbitt bearings inside the end of the drive shaft torque tube. I also do not know just when that change took place, or if it was the same time or different as the Babbitt differential bearings were changed. I read these thing so often, but yet I doubt the accuracy of most of what I read (can you say "cynical"), so I don't try to memorize all the details and timelines unless there is sufficient corroboration to warrant memorization.
And of course further improvements were made switching to twelve rivet early for 1912, then twelve rivet onto a cast differential housing late in 1912 model year (which was used for about two and a half years into early 1915). Eventually in early 1915, the long-running (more or less permanent) differential design in early calendar '15.

As a point of example. Some years ago, I needed to do considerable repair work on an engine pan. I had a damaged (broken and bent) pan that donated a couple required pieces, leaving me with a really bad parts pan. I wound up using some other materials out of that pan for other things I needed to make or repair. The pan was a complicated stamping, and partially an extruded piece. It was interesting cutting pieces off of it, and reshaping the material to fit what I was repairing. Variations in thickness became obvious. And some areas worked like soft butter, while others were tough and brittle form past work hardening. It made it easier for me to understand why the first long and wide extrusions did not work out well.