No idea what the gear ratio is. However speed is dependant upon which gear you are in and engine rpm, so therefore really and truly the gear ratio also changes as you change gear.
Max pulling power is governed by what size shear pin you put in the pto, but as most tend to just put a high tensile bolt in there really isn't a quoted rating. Suffice to say it is enormous!
These winches will pull all day long so long as your engine is running, as there is no motor etc to get hot. They will pull a house down, but they are slow.......frustratingly slow.....because of this it becomes impossible to drive assist with one of these winches - you have to run the transfer box in neutral. Spooling cable back in after winching is painfully slow also.
They are incredibly heavy, and spares are unavailable so make sure that you have all the parts, including all the pto rods, centre bearings etc.
I used to have one of these winches, but sold it in eventually and replaced it with an Uprated warn 8274. I wouldn't go back to the mayflower.
Jon