Ford AOD Fairbanks Superior Transmission Posi Shift 2 Stage Kit 1980-92 This 2 Stage Shift Kit from Superior comes with two levels of performance: 1. Heavy Duty 2. Street & Strip This shift kit firms up all gears (2nd, 3rd, 4th), provides proper shift timing, cleans up 3-4 & 4-3 shifts, replaces worn out separator plate with the new special design plate, and improves overall performance. The Posi Shift 2 Stage Pac's are by far the easiest available way to step up transmission performance and can be installed with the transmission in or out of the vehicle.