I don't claim to be an engineer, but I have to wonder why we need two OD gears? I'd rather have the rpm spread broken up more in the previous 5 gears and give me one OD with a reasonable ratio. My 4 spd dinosaur only has one OD and it runs fine that way for the most part. I do lock it out many times on hilly routs, so I'm fine with some rpms. I just fail to see why they make them overly complex with extra gears then ad an extra OD. I'd gladly take an extra gear between 1st thru 5th or 6th, then have one OD. Prolly all about fuel economy, but it it won't pull either of the OD without down shifting into "D", what's the point? If I want a sizable jump between any gears, put it between OD and the last gear before OD. It's going to shift out of OD anyhow.