CMS

CMS for Porsche

We specialize in Porsche transmissions, manufacturing many components and upgrades. CMS have served the Porsche community for over 35 years and continue to do so.

A Quick Look at CMS

We specialize in Porsche transmissions, manufacturing many components and upgrades. CMS have served the Porsche community for over 35 years and continue to do so.

Choosing the Right Fit for Your Porsche

Where CMS is listed for Porsche, use the supplied model coverage and OE references to confirm suitability. Check details that commonly affect fitment such as model year, side/position, and connector type where relevant.

• Typical reasons to choose these parts include repairing wear-related issues cost-effectively and restoring normal road-use performance without stepping up to premium-price options.
• Common triggers for replacement include tired bushes or joints, squeaks, knocks, leaks, and vague handling, sometimes caused by worn mounts, old fluid, misalignment, or corrosion.
• Check the specification and any OE cross-reference on each part listing rather than assuming all items are OE-equivalent.
• When working on suspension, braking, or drivetrain assemblies, it is often wise to renew related components at the same time and to follow correct alignment and torque procedures.

Browse by Category

If you already know the area you are working on, start with the category and then filter by Porsche model. Where real-world symptoms and typical reasons to replace are provided, use them to keep the wording grounded.

Gearbox / Transmission — You change gearbox and transmission parts when there are shifting issues, noise, leaks, or you are refreshing a high-mileage drivetrain. It is also common during upgrades such as stronger clutches or different ratios, where compatibility with manual, Tiptronic, or PDK systems and correct tolerances is essential. Common symptoms include whining in a specific gear, crunching on shifts, difficulty selecting gears, and leaks at seals or casing joins.

• Rule out simpler causes first, such as incorrect or old oil, worn mounts, or external linkage issues, before assuming the gearbox itself is at fault.
• When servicing or diagnosing, consider oil change and inspection for metal particles as an early, relatively low-cost check.

Gearbox Parts — Gearbox internal parts are typically replaced to cure bearing, synchro, or seal wear, to rebuild after noise or shifting issues, or to support higher power and long-term reliability. They are also frequently renewed during restorations where age, contamination, or corrosion has taken its toll. Common symptoms include whining, notchy or crunching shifts, popping out of gear, and leaks at seals or casing joints.

• Use the correct oil specification for your gearbox, as unsuitable lubricants can worsen synchro performance and accelerate wear.
• During a rebuild, it is good practice to replace seals, mounts, and any tired linkage components at the same time to reduce the risk of repeat issues.

Selector Forks / Shafts — Selector forks and shafts are replaced when bent, worn at their contact pads, or when scoring and play affect accurate engagement. They are crucial to clean, positive gear changes and to preventing gears from partially engaging or jumping out under load. Typical symptoms include gear pop-out, difficulty or blockage when selecting certain gears, and grinding caused by partial engagement.

• Be aware that worn forks and shafts can mimic synchro problems, as they may prevent full engagement even if the synchroniser is serviceable.
• During gearbox work, also check detent mechanisms, hubs and sleeves, plus external linkage adjustment and bushes for a complete diagnosis.

Side Cover Plate — Side cover plates are commonly replaced to fix persistent gearbox oil leaks, warping, or damage that affects bearing support and sealing. They help retain oil, maintain correct alignment, and prevent contamination entering the gearbox. Visible corrosion, distortion, stripped threads, and repeated seepage around the cover are typical warning signs.

• If leaks continue after gasket or sealant replacement, inspect the cover carefully for warping or damage to the sealing face.
• During reassembly, ensure clean, flat mating surfaces, the correct torque sequence, and replace any corroded or stretched fasteners where necessary.

Motor Sport Parts — Motorsport transmission parts are chosen to improve durability, performance, and consistency under hard use such as track days or competition. They are designed to cope with higher torque loads, heat, and rapid shifts, often trading refinement for strength and response. Downsides can include more noise and vibration, a harsher feel, and more frequent fluid changes and inspections.

• Confirm whether any motorsport-oriented components are suitable for road use in your region, as some upgrades are designed solely for track or competition.
• Plan for increased maintenance intervals with high-performance parts, paying close attention to fluid condition, temperatures, and any changes in noise or feel.

Explore CMS at Design911

View the current CMS range for Porsche at Design911, then filter by model and category to narrow down to the right parts.