Found this that is a good read. Prior to 1985, all F-250 HD and F-350 4X4’s came with the Twin Traction Beam (TTB) front axle. The F-250’s had reverse cut Dana 44’s up until 1987 with the Dana 50 optional. Most F-250 SuperCabs came with the D50 due to the added weight. The D50 became standard in 1987. During this same timeframe, the F-350 came standard with the D50 TTB up until 1985. In February of that year, the Dana 60 solid axle became standard front fare on all F-350 models and remained the standard for years to come.
Axle ratios were limited to 3.54: and 4.10:1 and transmission options were the Borg Warner T-19 four speed and Ford’s own corporate C-6 automatic. It’s interesting to note that the 4.10:1 equipped trucks had a 14,000 pound gross combined vehicle weight (GCVW) while the 3.54:1 equipped trucks were limited to 13,000 pounds for the manual; and 12,000 pounds for the automatic. All 4X4 models came with the Borg Warner 1345 transfer case.