Zonxin Semi-Trailer Disc Axle User Manual

Ⅲ. Disc Axle Maintenance and Service

1. Maintenance Schedule

● Indicates maintenance required

Note: Due to differences in regional road conditions and axle application environments, the following maintenance schedule is for reference only.

2. Axle Lubrication

Note: Ensure all tools and containers are clean when changing or adding lubricant.

Hub Bearing Cavity Lubrication:
Every time brake pads are replaced, and at least once every six months or after 50,000 km, remove the wheel, thoroughly clean the bearings, hub cavity, and seals. Replace any damaged parts and apply grease.

Apply 3–6 mm of grease to the hub cavity.

Apply 5–6 mm of grease to the inner and outer bearing rings.

Important: The roller space in the bearing cone must be completely filled with grease.

3. Maintenance Precautions

(1)The new brake disc thickness is 45 mm. It must be replaced when worn to the minimum thickness of 37 mm.

(2)Inspection must be performed with the vehicle in an unloaded and parked condition. When lifting the vehicle, the axle must be lifted simultaneously.

(3)In cold regions or wet conditions, if the axle and brakes are frozen due to water immersion or washing, use hot water to remove ice. Open flames are strictly prohibited to prevent damage to the brake, tone ring, or sensor.

(4)When lifting the wheel with a jack, position it near the guide leaf spring bracket. Do not lift directly under the axle tube. Place a thick steel plate between the jack and axle to avoid deformation or slippage.

(5)When replacing brake pads, if the disc thickness is close to 39 mm, replacement of the disc is recommended. Both sides of the same axle should be replaced simultaneously. Brake pad replacement is recommended when replacing the disc.

(6)If disc runout exceeds 1.5 mm, the disc must be resurfaced or replaced.

4. Checking Wheel Nut Tightness

(1)After initial loaded driving and again 15 days later, or after each wheel replacement, tighten the wheel nuts with a torque wrench in a crisscross sequence to the specified torque.

(2)If a common wheel wrench is used, an extension pipe should be added to achieve the specified torque. A torque wrench is strongly recommended.

5. Inspecting Hub Bearing Condition

Inspection frequency: every 6 months.

Lift the axle so the tire is off the ground. Insert two pry bars between the tire and ground to check for abnormal bearing play. If any irregularity is found, adjust immediately. At the same interval, use a special socket and torque wrench to check whether the hub cap is loose.

Bearing Adjustment Procedure:

(1)Loosen the hub cap.

(2)Remove the cotter pin from the axle nut.

(3)While rotating the hub, tighten the nut using a special octagonal socket and torque wrench to 350–400 N·m. If a torque wrench is not available, tighten until slight resistance is felt when rotating the hub by hand.

(4)Loosen the nut by 1/8–1/6 turn, align the nut slot with the axle hole, and insert the cotter pin. Install the hub cap with seal and tighten.

6. Regular Inspection of All Components

Inspect tires for uneven wear every 3 months.

Inspect all components for damage and wear every 6 months.

(1)Bearings must be replaced if any of the following conditions occur:

①Severe rotor wear

②Bearing damage, cage or roller cracks, or corrosion

(2)Brake discs must be replaced if:

①Wear reaches 37 mm thickness

②Disc lateral runout exceeds 1.5 mm