Transmissions | Clutches | Drivetrains, , 0 UD UD637 Differential Assembly (Rear, Rear), RECONDITIONED DIFFERENTIAL UD637 637 RATIO 42 SPLINE AXLE NO CORE CHARGE OUTRIGHT SALE 6 MONTH WARRANTY QUESTIONS CALL KEVIN DUSTIN @ 800-247-4313 EXT 1123, USED