M5R1 M5OD M5R2 5spd Transmission Countershaft Nut Part # M5R1-167 Will fit: M5R1 Ford Aerostar 1985 - 1995 Ford Explorer 1991 & up Ford Bronco II 1988 - 1990 Ford Ranger 1988 - Up Ford Explorer Sport & Sport Trac 2001 - 2002 M5R2 Ford Full Size Pick-up 1988 - up Ford Bronco 1988 - 1992 Ford Econoline 1988 - 1989 Identify this Transmission by Tag's on the side "E87A, E97A, FO7A, F17A " This Transmission has an Aluminum Case and an Aluminum Top Cover. Note it is called M5R1, M5R2 or M5OD or Mazda Type.