were any of the 5 speeds that were offered overdrive? and if so how interchangeable are they with the 4 speeds? The truck i'm looking at purchasing (haven't heard from the owner since I made a offer)has a two speed rear axle and the high gear is 5.83 if i'm reading this correctly and that would not be very conducive to highway speeds,

even with 900x20's. Anyone able to decipher the rear axle info?