OICA comments on SG4 Use Phase inputs to GRPE/2025/17 concern vehicle service life definitions, discrepancy and deterioration factors for real-world energy consumption, battery state-of-health degradation for off-vehicle charging hybrid electric vehicles, hydrogen and methane leakage quantification, refrigerant emissions from air conditioning systems, and maintenance parts replacement methodologies. OICA advocates for regional flexibility in service life determination, OEM-specific data for discrepancy factors at Level 4, standardized approaches for battery and fuel cell deterioration, and structured hierarchies for assessing maintenance part replacements over vehicle operational lifetime.