Rear differential leaks fluid

Probable Cause 

• Fluid level too high
• Clogged breather hose
• Worn or damaged oil seal
• Damaged sealing washer
• Loose mounting bolts or inadequate sealing

Remedy 

• Lower to proper level 
• Clean or replace
• Replace the oil seal 
• Replace the sealing washer 
• Recheck torque or apply sealant