What Causes the Rear Axle Humming Noise When a Van is Running?

[VanMolly]

For the specific reasons why a van's rear axle makes a humming noise when running, the following are possible causes: 1. The exhaust pipe is detached. A loose exhaust pipe can easily vibrate at high speeds, producing abnormal noises. Solution: Simply re-secure the exhaust pipe. 2. The differential is damaged. Misalignment of gears inside the differential causes friction, leading to abnormal noises. Solution: The gear clearance needs to be readjusted. 3. The differential bearings lack lubrication. Misalignment of gears inside the differential causes friction, leading to abnormal noises. Solution: Apply lubricating oil for lubrication. 4. The differential bearings lack lubrication, and the differential has cracked due to impact. Solution: Replace with a new differential.