Gearbox mount. Porsche 996 / 997 Rear (EXTENSION HOUSING)  ›  99637505505

The OE Match Rear Gearbox Mount is a replacement transmission mounting component designed for the extension housing of Porsche 996 manual gearboxes.

• Porsche 996 C2 3.4L 1997-08/01
• Porsche 996 C4 3.4L 1997-08/01
• Porsche 996 C2 3.6L 09/01-2005
• Porsche 996 C4 3.6L 09/01-2005
• Porsche 996 C4S 3.6L 09/01-2005
• Porsche 996 TURBO 2000-05  

The gearbox mount supports and locates the transmission within the vehicle while using its rubber-isolated construction to absorb vibration and driveline movement. It allows a controlled amount of movement while preventing the gearbox from shifting excessively under acceleration, braking, gear changes and changing engine loads.

A healthy gearbox mount is important for maintaining correct drivetrain alignment and preventing unwanted movement from being transmitted into the chassis. As the original rubber deteriorates with age, heat and repeated loading, the mount can soften, crack or separate, allowing excessive gearbox movement.

What This Product Does:

• Supports and locates the gearbox within the vehicle.
• Connects the transmission extension housing to its mounting structure.
• Controls excessive transmission movement under load.
• Absorbs vibration generated by the engine and drivetrain.
• Helps isolate drivetrain vibration from the vehicle body.
• Maintains more consistent drivetrain alignment.
• Reduces movement during acceleration and deceleration.
• Helps maintain a more precise feel during gear changes.
• Reduces stress on surrounding drivetrain components and mountings.
• Replaces an original mount that has softened, cracked or deteriorated.

The rubber section of the mount is designed to provide a balance between securely supporting the gearbox and isolating normal drivetrain vibration from the chassis.

Symptoms Of Wear Or Failure:
A deteriorated gearbox mount can allow the transmission to move more than intended. Possible symptoms include:

• Clunking or knocking during acceleration or deceleration.
• Excessive drivetrain movement when applying or releasing the throttle.
• Increased vibration through the cabin.
• Vibration through the gear lever.
• Movement of the gear lever as engine load changes.
• Harshness when pulling away.
• Increased noise during gear changes.
• A noticeable thump when changing gear.
• Reduced precision or consistency when shifting.
• Drivetrain vibration at certain engine speeds.
• Contact or rattling from nearby exhaust or drivetrain components.
• Visible cracking or splitting of the rubber mount.
• Rubber separating from the metal mounting sections.
• Sagging or distortion of the mount.
• Excessive gearbox movement when inspected.

These symptoms can also be caused by engine mounts, transmission components, suspension parts or other drivetrain issues, so the mounting system should be properly inspected before replacement.

Why Replacement Matters:
Gearbox mounts operate continuously under the weight and movement of the transmission while also dealing with torque reactions from the engine and drivetrain.

Over time, repeated loading, heat and ageing can cause the rubber element to harden, soften, crack or separate. Once the mount can no longer control gearbox movement effectively, the transmission may move excessively when engine torque is applied.

This can result in increased vibration, knocking noises and a less precise drivetrain feel.

Replacing a worn gearbox mount helps:

• Restore controlled gearbox movement.
• Reduce knocks and clunks from the drivetrain.
• Reduce unwanted vibration.
• Improve drivetrain stability.
• Maintain more consistent gearbox alignment.
• Improve gear-change feel.
• Reduce unnecessary movement of the gear lever.
• Protect surrounding mountings and drivetrain components.
• Restore the refinement expected from the vehicle.