I got the code on the door B6 and found a Ford Code List: 19 — 3.55 non-limited slip (Econoline, F-150) 18 — 3.08 non-limited slip (F-150) 17 — 3.31 non-limited slip (Econoline) H9 — 3.55 limited slip (F-150, F-250) B6 — 3.73 limited slip (F-150, F-250) 24 — 3.73 (Econoline) 32 — 4.10 (Econoline) 35 — 4.09 (Econoline) 34 — 3.73 (Econoline) 39 — 3.55 (Econoline) 52 — 4.10 (Econoline) 56 — 4.10 (Econoline) 81 — 4.63 (Econoline) 27 — 3.31 non-limited slip (F-250) 26 — 3.73 non-limited slip (F-250) 41 — 3.27 non-limited slip (Explorer/Mountaineer) 45 — 3.55 non-limited slip (Explorer/Mountaineer) 46 — 3.73 non-limited slip (Explorer/Mountaineer) 42 — 4.10 non-limited slip (Explorer/Mountaineer) D1 — 3.27 limited slip (Explorer/Mountaineer) D4 — 3.73 limited slip (Explorer/Mountaineer) D2 — 4.10 limited slip (Explorer/Mountaineer) 84 — 3.45 non-limited slip (Ranger) 86 — 3.73 non-limited slip (Ranger) 87 — 4.10 non-limited slip (Ranger) 89 — 4.56 non-limited slip (Ranger) F6 — 3.73 limited slip (Ranger) F7 — 4.10 limited slip (Ranger) 92 — 3.08 non-limited slip (Ranger) R5 — 3.55 limited slip (Ranger) 91 — 3.27 non-limited slip (Ranger) 96 — 3.73 non-limited slip (Ranger) R6 — 3.73 limited slip (Ranger)" 19 --3.55 non-limited slip (Expedition) 17 --3.31 non-limited slip (Expedition) H9 --3.55 limited slip (Expedition) H7 --3.31 limited slip (Expedition) H6 --3.73 limited slip (Expedition) So is the front and back the same? Are they both LSD and POSI ?