The maintenance and inspection process for the idler of a dozer after adding gear oil primarily includes the following steps:

1. Check Oil Quality and Level: First, it is essential to verify that the added gear oil meets the dozer's specifications and that the oil level is adequate. This step is fundamental and critical, as improper lubrication can lead to severe mechanical damage.

2. Clean and Inspect the idler Shaft: Use sandpaper to remove rust from the surface of the dozer idler shaft and check for any damage in the tip hole. If any damage is found, repairs should be carried out.

3. Align the dozer idler Shaft: Insert one end of the idler shaft into the inspection instrument's turntable hole, and measure the shaft's runout using a dial indicator. If the runout exceeds 2 mm, realignment is necessary.

4. External Maintenance: Inspect all components of the steering system, including the steering wheel, steering mechanism, and operational performance. Also, check for any signs of oil leakage.

5. Internal Maintenance: Conduct a thorough inspection and necessary maintenance of all components within the steering mechanism. This includes checking the gears and other critical parts to ensure they are in good working condition.

6. Observation and Documentation: Throughout the maintenance process, detailed records of all inspections and repairs should be maintained for future reference and further maintenance tasks.