The axles for Jeep conversion we are keen on are the 96 through 2001 Ford Explorer and Mercury Mountaineer with disc brakes and all that fall into this category with or without limited slip have the 7/8 inch cross pin. Convert from a 28 to a 31 spline??? Need bigger axle tubes too! The bearing on a 31 spline is much bigger than a 28 spline bearing. More @Wikipedia
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