gear's?

[TCASON]

I'm looking at getting my grandfathers 68 1/2 ton with a 307 2wd auto, from an older brother who has let it sit for 10 yrs. Was going over some ?s with him on the condition, and he mentioned that when he had last driven it, it sounded to him that it was running pretty hard at @ 60mph. He believes that it has some very low gears, but has no idea what they may be.
My grandfather bought it used with low miles for his farm.
Anyone have some idea's on the gearing?