After rebuilding a differential with junkyard parts, user has a low knock/rumble on deceleration and is uncertain whether the pinion depth, backlash, or stress cracks on gear teeth are causing the issue.

Workarounds Described

• Relies on forum feedback to interpret gear pattern and noise
• Manually cross-references backlash spec from service manual
• Visually inspects gear teeth for cracks with naked eye or camera

Implied Software Gaps

• AI-powered gear pattern analysis tool that provides definitive depth/lash adjustment guidance
• Integrated vehicle-specific backlash spec database with tolerance check
• Automated photo-based crack detection on gear teeth

DiffDiagnose Pro

A mobile app that helps DIY mechanics and small shops diagnose differential issues by analyzing ring and pinion pattern photos, backlash measurements, and noise characteristics. It provides step-by-step guidance on whether to adjust depth, tighten lash, or replace gears, reducing guesswork and repeat disassembly.