Hose Clamp Genuine Porsche part 99951234901

• 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)  

• Secures heater hoses to pipes, fittings and cooling system components.
• Maintains a leak-free coolant system connection.
• Provides consistent clamping force under varying temperatures.
• Prevents hose movement caused by vibration and pressure changes.
• Supports efficient coolant circulation through the heating system.
• Helps maintain correct cabin heating performance.
• Contributes to overall cooling system reliability and safety.

• Coolant leaks around heater hose connections.
• Visible corrosion or rust on the clamp.
• Loose or slipping heater hoses.
• Coolant residue around hose fittings.
• Reduced heater performance due to coolant loss.
• Sweet coolant odour from the engine bay.
• Low coolant level warnings.
• Overheating concerns caused by coolant leakage.
• Visible clamp deformation or loss of tension.

• Heater hose clamps are exposed to continual heat cycles, moisture, coolant chemicals and engine vibration. Over time, corrosion, metal fatigue or loss of clamping tension can reduce their ability to maintain a secure seal between hoses and cooling system components.
• A failing hose clamp can allow coolant to escape, leading to reduced heater efficiency, cooling system pressure loss and potential engine overheating. Even minor coolant leaks can worsen over time, increasing the risk of damage to cooling system components and resulting in costly repairs.
• Replacing a worn or damaged heater hose clamp restores proper hose retention, prevents coolant leaks and helps maintain the efficiency and reliability of the cooling and heating systems. An OE Match replacement provides factory-style fitment, dependable clamping performance and long-term durability, ensuring reliable operation of your Porsche cooling system.

Water Cooling Pipe System Upgrade

The OE Match Water Cooling Pipe System Upgrade is a permanent solution to one of the most common and well-known cooling system failures affecting the first-generation Porsche 955 Cayenne 4.5L V8 S and Turbo models built between 2003 and 2006.

Fits:

• Porsche 955 Cayenne S 4.5L V8 2003-06
• Porsche 955 Cayenne Turbo 4.5L 2003-06
• Porsche 955 Cayenne Turbo S 4.5L 2006>>

Diagram ref Nos 7, 9, 10, 11, 12, 13, 16 and 17

The original factory cooling system uses a series of plastic coolant pipes located beneath the intake manifold to carry coolant between the engine block, thermostat housing and cylinder heads. While perfectly adequate when new, years of repeated heat cycles cause these plastic pipes to become brittle and lose their structural integrity. Eventually they can soften, crack or separate from their bonded joints, leading to sudden coolant loss and rapid engine overheating.

Porsche later introduced an improved aluminium pipe design to eliminate this weakness. This OE Match upgrade kit replaces the original plastic coolant pipes with durable alloy replacements, providing a long-term repair that is far more resistant to heat, pressure and age-related deterioration.

A failed coolant pipe can result in coolant leaking into the engine valley beneath the intake manifold, where it may initially go unnoticed. Drivers often first discover the problem through unexplained coolant loss, coolant odours, warning messages or engine overheating. Continuing to drive with a leaking pipe can lead to severe engine damage, making early replacement a wise preventative maintenance upgrade.

Replacement is strongly recommended if the intake manifold is already being removed for other engine work, such as starter motor replacement, knock sensor replacement or general engine servicing. Many owners also choose to install the alloy upgrade proactively once their Cayenne reaches higher mileage or shows signs of cooling system deterioration.

Features & Benefits

• OE Match alloy water cooling pipe upgrade kit
• Replaces the original plastic coolant pipes
• Eliminates a common failure point on early 4.5L V8 engines
• Improved resistance to heat and coolant pressure
• Reduces the risk of sudden coolant loss and engine overheating
• Ideal preventative maintenance upgrade
• Suitable for Porsche 955 Cayenne 4.5L S and Turbo models (2003-2006)
• Direct replacement for the original cooling pipe assembly

Porsche 955 Cayenne Alloy Water Cooling Pipe Upgrade

The first-generation Porsche Cayenne is renowned for its performance and versatility, but owners of the early 4.5-litre V8 models are often familiar with the factory plastic coolant pipe issue. Upgrading to the later alloy pipe design is widely regarded as one of the most important preventative maintenance improvements for these vehicles.

At Design911, we supply high-quality OE Match cooling system components that restore reliability while maintaining original fitment standards. Whether you're carrying out preventative maintenance, repairing a coolant leak or rebuilding your engine, this alloy coolant pipe upgrade offers lasting peace of mind.

Why Upgrade to Alloy Coolant Pipes?

Unlike the original plastic pipes, alloy pipes are unaffected by prolonged exposure to engine heat and pressure. Once installed, they provide a significantly more durable cooling system capable of withstanding the demanding operating temperatures of the Porsche V8 engine.

Common Symptoms of Failing Plastic Coolant Pipes

• Unexplained coolant loss
• Coolant smell after driving
• Coolant pooling beneath the intake manifold
• Low coolant warning messages
• Rising engine temperatures or overheating
• Steam from the engine bay

Replacing the plastic coolant pipes before failure helps avoid costly overheating repairs and significantly improves long-term engine reliability