Technical Specifications for Motor Vehicle Maintenance, Inspection and Diagnosis (GB/T 18344)

GB/T 18344 "Technical Specifications for Motor Vehicle Maintenance, Inspection and Diagnosis" serves as a core recommended national standard within China's automotive servicing and repair industry. It establishes unified technical guidelines for the maintenance, testing, and fault diagnosis of all in-use motor vehicles.

📜 Standard Overview

🎯 Scope of Application

• Applicable Models: Covers all in-use motor vehicles (including new energy vehicles / NEVs) powered by petrol or diesel.

• Reference Execution: Trailers and semi-trailers may refer to this standard for execution.

• Exclusions: Does not cover specific operational requirements designed for special-purpose vehicles.

🧱 Key Highlights

The standard sets out strict technical regulations across four essential operational pillars:

1. Maintenance Classification

Vehicle servicing is clearly categorized into three distinct tiers:

• Routine Maintenance: Daily checks conducted by drivers before departure, en route, and after trips, focusing on cleanliness, fluid top-ups, and basic roadworthiness inspections.

• Level 1 Maintenance (Minor Service): Periodic servicing carried out at professional workshops, centering primarily on cleaning, lubrication, and fastener torque checking.

• Level 2 Maintenance (Major Service): Comprehensive in-depth servicing; in addition to Level 1 tasks, it mandates inspection and calibration of critical safety systems such as brakes and steering, alongside tyre rotations.

2. Service Intervals

A key revision in this standard is moving away from the conventional "one-size-fits-all" fixed-interval schedule in favour of "condition-based on-demand maintenance" . Service schedules must be tailored based on six core criteria:

Vehicle classification, operating duty cycle, environmental conditions, OEM recommendations, technical wear status, and replacement parts quality

Workshops are required to draw up bespoke servicing schedules for each vehicle, display the service intervals prominently on premises, and furnish written notifications to vehicle owners.

3. Critical Operational Requirements

The latest standard introduces stringent requirements across several core systems:

• Engine System: Engine oil and oil filters must be renewed concurrently; long-life coolant is recommended for replacement every 5 years or 100,000 km.

• Chassis System: Brake fluid must be flushed and replaced every 2 years or 40,000 km; brake pads must be replaced once friction material falls below 3 mm.

• Tyres: Compulsory structural and rubber degradation checks are mandatory once tyres reach 5 years of service.

• Electrical & Electronic Systems: Certified diagnostic scan tools must be utilised for scanning and clearing fault codes (DTCs). New dedicated inspection protocols have been added for electrified vehicles, focusing on high-voltage safety systems and battery thermal management.

• Post-Service Inspection: Following Level 2 Maintenance, vehicles must undergo comprehensive roadworthiness testing covering braking efficiency and exhaust emissions, and can only be released after receiving an electronic vehicle pass certificate.

4. General Compliance

• Technician Credentials: Mechanics and technicians performing Level 1 and Level 2 servicing must hold valid professional certifications.

• Archiving & Record Retention: All servicing logs, job sheets, and inspection records must be digitised and retained for a minimum of 3 years to guarantee end-to-end traceability.

⚖️ Key Upgrades: Old vs New Standard

Compared with the previous 2016 framework, the 2025 standard brings several notable revisions:

1. Optimised Service Cycles: Shifted from rigid "fixed mileage/duration" schedules to dynamic on-demand maintenance.

2. Broader Scope: Technical provisions have been explicitly expanded to cover electrified and new energy vehicles.

3. Higher Benchmarks: Stricter criteria introduced for technician competency, workshop diagnostic equipment, and standard operating procedures (SOPs).

4. Digitised Compliance: Enforced digital log keeping, with a mandatory minimum retention window of 3 years.

💎 Summary

GB/T 18344-2025 serves as an authoritative "industry blueprint" driving best practices in automotive servicing and maintenance. By incorporating condition-based on-demand servicing, introducing dedicated EV standards, and tightening job accountability, the ultimate aim is to ensure road safety, extend vehicle service life, and minimise vehicle emissions.