Bruce stated that the frame rear cross member was a simple channel (inverted "U") then changed to a flanged rear cross member (hat cross section). Does anyone know at what time the change took place?
Second statement was in 1927 a heavier frame was used for increased strength. Does anyone know at what time (month) or at what engine serial number did that change take place?
Dates weren't given, but he says early for the simple plain crossmember, 2854C (Fac # 2913B) for the '26-'27 style.
A trip to the Benson Ford would have to be done to get the change order sheet on the Fac # 2913B wide crossmember.
Early '26 frame, guess the dates are Aug to Oct '25.
Later frame with U shape and bolt holes in the U for the rear spring hangers.
My Nov '25 mfg. Improved Car runabout had this later style frame. The heavier frame would have been in the '27 model year, after July 1926.
According to the encyclopedia, the heavier gauge frame was earlier than 27 model year, more like march 1926:
"By February 28 there was a note to the Midland Steel Products Parish and Bingham division to stop shipping frames until the rails could be made of "Type L" steel with a thickness of .180 to .200 inches. The Ford engineers suggested using the same gauge stock as was used on the ton-truck frames."
Type L steel was pretty plain-Jane with a medium carbon content (.23-.30%). No chrome, nickel or vanadium. Not even silicon. Any one know what steel type was used before "Type L"?