C) 1976, switched to disk brake fronts, has "small" knuckle pattern for steering arms, slightly smaller birfields than later models so still slightly weaker. 4.10 gear ratio. Usually had weaker Warn hubs or other aftermarket (but usually Warns) installed at dealer compared to later Aisins but there are a few Aisins. In mid-late '78, there are a few pinions that were changed to fine spline making them stronger versus earlier models. All diffs still interchangable.
D) 1979, switched to bigger knuckle pattern, bigger birfield which would remain through 1989-1990 through end of 62 series that is also the same in minitrucks. Used a larger knuckle pattern for steering arms, also the same for mini trucks. Is the strongest. Switched to faster 3.73 axle gear ratio.
E) FJ60 models only: same as D but 2.75" wider.
F) 70 series models, same as D but I think 30 mm wider so about an inch wider?
G) FJ62 models only. Same as E but pinion angle was rotated up about 8 degrees towards T-case making for a "factory cut and turn" (still barely enough for a spring over but usable and better than no cut and turn). Gear ratio was returned to 4.10 but they have fine spline count so stronger. Also, axle is factory trussed, and disk brakes have a little wind scoop for better cooling.
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