Our gear box remanufacture would put up quite an argument in favor of a 3.5 turn box vs a 4.25 turn box. All of ours are dual stage valving, and evidently we can actually get better valving in the 3.5 turn box. This is quite a techy subject though, not sure I'm qualified to discuss it???as stated yes that is the correct part number but still check that it is 4.25 turn lock to lock if its referbished. mine is the same part number but is about 3.25 lock to lock and its a refurbished unit.