Exactly what are the differences between the frame's front crossmembers. More specifically, what is the difference between one from a mid-20s frame and a 1915 (--or possibly earlier frame)?? How does one easily differentiate between them?
Good question! Early ones don't have Ford script. After that , I give up.
Earlier ones were thinner steel. I think they made them thicker about 1919, but I could be off a year or two. There were also changes in the offsets and dimples around the motor mount. However I don't know them well enough to help out much.
This is one of many pieces that I would like to see a really good study with good pictures for identification. From very early through the end (and don't forget the TT), the front cross-member changed in minor details only. Unless you are going for a trophy car? Any car model T front cross-member should work okay and be reasonably acceptable on an early car. I would avoid using the earlier thinner cross-members on later cars simply for strength reasons. I would use them on early cars for correctness reasons, but would also consider strength versus correctness in using later cross-members on early cars.
Just my opinion.
Drive carefully, and enjoy, W2
Older post on front cross members.
Bruce's research was the heavier cross member was done Dec. 1920. And then the script was stamped.
So an earlier than late 1920 would be thinner and no script.
Poor photo, accessory starter hides most of this true 1915 front cross member.
Later after 1920 cross member
Bruce says about March 19, 1919.
In addition, is the earlier crossmember a little deeper with regard to radiator tank clearance?