The Mack / Volvo Differentials MT40-14X is a rear differential listed for on-highway applications. Recorded for MT40-14X: brand Mack / Volvo, family Mack / Volvo Differentials, series CRD / RSS, axle position rear, application on-highway. Gear ratios, torque ratings, and interchange details are verified per unit against your tag or VIN rather than published here. Availability: Available Now.