Understanding Tow Truck Rear Axle Failures

All vehicles, after prolonged use, will inevitably experience some faults, and tow trucks are no exception. The load-bearing capability of a tow truck primarily depends on the rear axle. Therefore, it’s essential to pay attention to any abnormalities in the rear axle during regular use and address any issues promptly. What are some common rear axle failures in tow trucks? Let’s take a look:

1. Abnormal Noises from the Tow Truck Differential

Differential Gear Issues:

• If the tow truck drives well in a straight line but makes abnormal noises when turning, it could be a fault in the differential gears.

Differential Bearing Damage:

• A low, intermittent “humming” noise from the rear axle, especially when coasting at low speed, combined with slight vehicle body shaking, indicates a damaged differential bearing. The noise may not be noticeable at high speeds.

Loose Differential Casing:

• A metallic knocking noise when starting and slight shaking at the rear of the vehicle when turning suggests loose rivets or bolts fixing the differential casing.

2. Abnormal Noises from the Garraioa Reducer

Improper Gear Meshing:

• A “howling” noise at low speeds and a “hissing” noise during acceleration or deceleration are generally due to improper gear meshing clearance.

Gear Meshing Issues on Slopes:

• Abnormal noises when going uphill indicate gear meshing is inclined towards the gear root, requiring the driving gear to be moved outward. Noises when going downhill indicate meshing towards the gear tip, requiring the driving gear to be moved inward.

Gear Meshing Surface Damage:

• A “humming” noise from the rear axle while driving, especially with metallic friction sounds increasing with speed but decreasing or disappearing when coasting, indicates damage to the gear meshing surface.

Damaged Gear Teeth:

• A sudden, strong, rhythmic “clang clang” metallic knocking noise while driving, which disappears when coasting, indicates damaged or broken gear teeth, necessitating prompt gear replacement.

Bearing Installation Issues:

• A hot reducer casing, difficult starting, sharp noises, and knocking sounds from the driveshaft when coasting indicate improper or damaged bearing installation.

3. Abnormal Noises from the Tow Truck Half Shaft

• Sudden abnormal noises while driving, inability to start, and the driveshaft rotating without vehicle movement when re-engaging gear indicate a broken half shaft.

The rear axle is the driving axle of the tow truck. It is crucial to remember the symptoms of these faults. Ignoring them can lead to significant failures and unnecessary losses.

Additional Tips for Rear Axle Maintenance

Regular Inspection:

• Regularly inspect the rear axle components for wear and tear. Look for signs of leaks, abnormal noises, or physical damage to the axle and its components.

Proper Lubrication:

• Ensure that the rear axle and differential are properly lubricated. Use the manufacturer-recommended lubricants and check the levels regularly.

Timely Repairs:

• Address any issues promptly. Small problems can escalate quickly, leading to more extensive damage and costly repairs.

Professional Maintenance:

• Seek professional help for complex issues. While some maintenance tasks can be done by the driver, others require specialized tools and expertise.

By maintaining the rear axle properly and addressing any abnormalities promptly, you can ensure the longevity and reliability of your tow truck, preventing significant failures and avoiding unnecessary losses.