Case Study: Fixing Toyota Drive Shaft Oil Leak (Prevent Gearbox Failure) | Advance Auto Work JB Case Study: The "Small" Leak That Kills Gearboxes (Toyota Drive Shaft Seal) At Advance Auto Work , we often see car owners ignoring small oil spots on their garage floor. In this case study, a Toyota owner brought their car in due to a wet undercarriage. Our diagnosis revealed a leaking Drive Shaft Oil Seal . The Diagnosis: Why was it leaking? It wasn't just old rubber. We found that the connection between the drive shaft and the gearbox was loose and shaky . This excessive vibration caused the seal to tear, allowing transmission fluid (ATF) to escape. The Fix & The Saving If the owner had ignored this, the gearbox would have run dry, overheated, and failed—costing RM 3,000+ to replace. Instead, we performed a Preventive Repair : Replaced the Drive Shaft Oil Seal with a high-quality component. Secured the Drive Shaft connection to stop the vibration. Top-u...