Gearbox Casing / Casing Parts
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 911 1975-1977 3.0L Turbo (930)
- Porsche 911 1978-1989 3.3L Turbo (930)
Hexagon socket head bolt.
Fits:
Porsche 911 1978-1986
Porsche 928 1978-1986
Diagram ref no 11
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
9990640190C
The product you are viewing cross references to these numbers
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 928 4.5L 1978-82
- Porsche 928S 4.7L 1981-83
- Porsche 928S2 4.7L 1984-86
Hexagon socket head bolt.
Fits:
Porsche 911 1978-1986
Porsche 928 1978-1986
Diagram ref no 11
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
9990640190C
The product you are viewing cross references to these numbers
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 928 4.5L 1978-82
- Porsche 928S 4.7L 1981-83
- Porsche 928S2 4.7L 1984-86

Fits:
Porsche 911/912 1965-70
Click 'Zoom in' for large parts diagram.
Diagram ref no 2
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
90130139201
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
Only for vehicles without servo springs.

Fits:
Porsche 911 1972-76
Only for vehicles without servo springs.
excluding turbo
Click 'Zoom in' for large parts diagram.
Diagram ref no 1
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91530190109
The product you are viewing cross references to these numbers
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera

Fits:
Porsche 911 1987-89 - x2 required per vehicle.
Porsche 964 1989-94 - x1 required per vehicle.
Porsche 993 1994-98 - x1 required per vehicle.
*Please be advised, this part is for manual gearboxes only.
- Porsche 911 1987-1989 3.2L G50
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
- Porsche 964 (911) TURBO 3.3L 1991-93
- Porsche 964 (911) TURBO 3.6L 1991-93
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) GT2 1994-97
- Porsche 993 (911) TURBO S 1994-97
Porsche Gearbox Casings & Casing Parts | Strength, Precision & Thermal Stability for Reliable Transmission Performance
The gearbox casing is the structural foundation of your Porsche’s transmission system. It houses and supports all internal components — including gears, bearings, shafts, and seals — ensuring correct alignment, strength, and efficient operation. High-quality casing components are essential for maintaining gearbox integrity, preventing leaks, and reducing vibration or mechanical stress.
At Design911, we supply precision-engineered gearbox casings and casing components designed to meet or exceed original performance specifications. Manufactured from high-strength aluminium or magnesium alloys, each casing ensures excellent rigidity, heat dissipation, and dimensional accuracy.
Whether you’re rebuilding a classic 911 transmission, repairing a damaged casing, or upgrading for performance reliability, our range of Porsche gearbox casings and casing parts guarantees strength, fitment precision, and long-term durability.
What Do Gearbox Casings & Casing Parts Do?
The gearbox casing acts as a rigid housing that protects internal components from damage, contamination, and misalignment while maintaining lubrication and temperature control.
Core Functions:
- Provides structural support and alignment for all internal gearbox components.
- Protects gears, shafts, and bearings from debris and external damage.
- Maintains correct oil levels and internal pressure.
- Ensures efficient heat dissipation for optimal transmission operation.
- Prevents leaks through integrated seals and machined joints.
Without a properly functioning casing, gearbox alignment and performance can degrade — leading to premature wear, oil leaks, and even transmission failure.
Why Do Gearbox Casings & Components Fail or Get Damaged?
Gearbox casings are exposed to mechanical stress, vibration, and heat over time, which can cause fatigue, cracking, or oil leaks.
Common Causes of Failure Include:
- Cracks or fractures from impact or over-torqued bolts.
- Corrosion or oxidation, particularly on older magnesium casings.
- Warping due to overheating or poor heat dissipation.
- Damaged or worn sealing surfaces causing oil leaks.
- Incorrect assembly or misalignment during installation.
When the casing or its mating surfaces fail, it can cause oil leakage, misaligned gears, excessive noise, or internal component wear — compromising gearbox performance and reliability.
Why Replace Your Porsche Gearbox Casing or Casing Parts?
Replacing a damaged or worn gearbox casing ensures structural integrity, correct alignment, and proper sealing — vital for transmission efficiency and performance. Upgraded or remanufactured casings also enhance durability and thermal control in high-performance applications.
Key Benefits:
- Restores proper gearbox alignment and internal balance.
- Prevents oil leaks and contamination of internal components.
- Improves heat management and mechanical strength.
- Reduces vibration and driveline noise.
- Ensures long-term reliability during rebuilds or performance upgrades.
- Available for manual, automatic, and PDK Porsche transmissions.
A high-quality gearbox casing or replacement part is essential during transmission rebuilds to maintain correct tolerances and optimal drivetrain function.
Highlights
- Precision Porsche gearbox casings and casing parts.
- Manufactured from high-strength aluminium or magnesium alloys.
- Perfect fitment for Porsche 911, Cayman, Boxster, and classic models.
- Designed for strength, rigidity, and long-term reliability.
- Restores transmission efficiency and structural integrity.
- Ideal for rebuilds, repairs, or performance transmission upgrades.