Bellcrank (SN 308805 > W/ STRAIGHT ADJ. REPLACEMENT AXLE). PART NO: A-AR91812. Marked R70231 Dim A (1)For 60"-88", 53"-76", Dim B (2)60"-93" or 53"-79" axles. . MODELS: John Deere TRACTOR: 2440 (SN 308805 > W/ STRAIGHT ADJ. REPLACEMENT AXLE) John Deere TRACTOR: 2640 (SN 308805 > W/ STRAIGHT ADJ. REPLACEMENT AXLE).