Innova Crysta Gearbox Noise Problem Fix | गियरबॉक्स डिसमेंटल और रिपेयर

Job Description: Gearbox Overhaul for 4th Gear Noise Description Start: "In this video, I will show you the step-by-step process of dismantling an Innova Crysta gearbox to troubleshoot and fix a persistent 4th gear noise issue. We will look at internal gear wear, synchronizer rings, and needle bearings." Customer Complaint/Symptom The vehicle exhibits abnormal whining or grinding noise specifically when engaged in the 4th gear under load. No noise is reported in other gears, suggesting a localized component failure within the gear train or synchronizer assembly. Technical Diagnosis (Root Cause Analysis) During the inspection and disassembly of the manual transmission unit, the following potential causes for the noise were identified: Damaged Gear Teeth: Wear and tear or pitting on the 4th gear driving/driven teeth. Synchronizer Assembly Failure: Excessive wear on the 4th gear synchronizer ring or hub, causing improper mesh or "grinding" during engagement. Needle Bearing Fatigue: Deterioration of the needle roller bearing located beneath the 4th gear, causing radial play and noise under engine load. Excessive Shaft End-Play: Inadequate clearance or damaged thrust washers leading to gear misalignment. Repair Procedure (Dismantling & Remediation) Removal: The transmission unit was safely removed and externally cleaned to prevent debris contamination. Disassembly: Removed the transmission housing and oil pan. Carefully extracted the input/main shaft assembly. Removed the circlips and disassembled the 4th gear cluster, synchronizer hub, and sleeve using a specialized puller to avoid shaft scoring. Inspection: All gear teeth, bearings, and synchro-mesh cones were inspected for scoring, blueing (heat damage), or pitting. Replacement: All identified faulty components were replaced with Toyota Genuine Parts. Reassembly & Testing: The gearbox was reassembled ensuring all specified tolerances (end-play) were maintained. New gaskets and seals were installed, and the unit was filled with recommended transmission fluid to the correct level. Summary for Service Records Work Performed: Gearbox disassembly, inspection of 4th gear internal components, replacement of damaged needle bearings/synchronizer ring, and final road test. Status: Resolved; noise eliminated. Would you like me to include a checklist of the specific tools required for this procedure or the recommended torque specifications for reassembly?