Coolant Hoses - Radiator Section
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche Boxster 987 MKII 2.9L 2009-2012
- Porsche Boxster S 987 MKII 3.4L 2009-2012
- Porsche Boxster 981 2.7L 2012-16
- Porsche Boxster 981 S / GTS 3.4L 2012-16
- Porsche Boxster 981 Spyder 3.8L 2016

Fits:
Porsche 991.1 Carrera - 2012 to 2016
Porsche 981 Boxster - 2012 to 2016 incl. Boxster Spyder
Porsche 981C Cayman - 2012 to 2016 incl. Cayman GT4
Click 'Zoom in' for large parts diagram.
Diagram ref no 30
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99110676602
The product you are viewing cross references to these numbers
- Porsche Boxster 981 2.7L 2012-16
- Porsche Boxster 981 S / GTS 3.4L 2012-16
- Porsche 991.1 Carrera C2 3.4L (350Bhp) 2012-16
- Porsche 991.1 Carrera C2S 3.8L (400Bhp) 2012-16
- Porsche 991.1 Carrera C4 3.4L (350Bhp) 2012-16
- Porsche 991.1 Carrera C4S 3.8L (400Bhp) 2012-16
- Porsche Cayman 2.7L 981 2013-16
- Porsche Cayman S / GTS 3.4L 981 2013-16
- Porsche Cayman GT4 3.8L 2015-16

Pipe from the center mounted radiator to the left side radiator.

Fits:
Porsche 987.1 Boxster 2005-08 Tiptronic transmission
Porsche 987.2 Boxster 2009-12
Porsche 987C.1 Cayman 2005-08 Tiptronic transmission
Porsche 987C.2 Cayman 2009-12
Porsche 997.1 Carrera 2005-08 Tiptronic transmission
Porsche 997.2 Carrera 2009-12
Click 'Zoom in' for large parts diagram.
Diagram ref no 10
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99710663904
The product you are viewing cross references to these numbers
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche Boxster 987 MKII 2.9L 2009-2012
- Porsche Boxster S 987 MKII 3.4L 2009-2012
- Porsche 997 MK1 Carrera 2 3.6L 2005-08
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4 3.6L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08
- Porsche 997 MKII Carrera C2 3.6L 2009-12
- Porsche 997 MKII Carrera C4 3.6L 2009-12
- Porsche 997 MKII Carrera C2S 3.8L 2009-12
- Porsche 997 MKII Carrera C4S 3.8L 2009-12
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
- Porsche Cayman 2.9L 987C MKII 2009-12
- Porsche Cayman S / R 3.4L 987C MKII 2009-12


Fits:
For cars with centre radiator (option code: 153)
Porsche 991.1 Carrera 2012-16
Porsche 981 Boxster 2012-16
Porsche 981C Cayman 2014-16
Click 'Zoom in' for large parts diagram.
Diagram ref no 6
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99110663802
The product you are viewing cross references to these numbers
- Porsche Boxster 981 2.7L 2012-16
- Porsche Boxster 981 S / GTS 3.4L 2012-16
- Porsche 991.1 Carrera C2 3.4L (350Bhp) 2012-16
- Porsche 991.1 Carrera C2S 3.8L (400Bhp) 2012-16
- Porsche 991.1 Carrera C4 3.4L (350Bhp) 2012-16
- Porsche 991.1 Carrera C4S 3.8L (400Bhp) 2012-16
- Porsche Cayman 2.7L 981 2013-16
- Porsche Cayman S / GTS 3.4L 981 2013-16


Fits:
For cars with centre radiator (option code: 153)
Porsche 991.1 Carrera 2012-16
Porsche 981 Boxster 2012-16
Porsche 981C Cayman 2014-16
Click 'Zoom in' for large parts diagram.
Diagram ref no 7
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99110663901
The product you are viewing cross references to these numbers
- Porsche Boxster 981 2.7L 2012-16
- Porsche Boxster 981 S / GTS 3.4L 2012-16
- Porsche 991.1 Carrera C2 3.4L (350Bhp) 2012-16
- Porsche 991.1 Carrera C2S 3.8L (400Bhp) 2012-16
- Porsche 991.1 Carrera C4 3.4L (350Bhp) 2012-16
- Porsche 991.1 Carrera C4S 3.8L (400Bhp) 2012-16
- Porsche Cayman 2.7L 981 2013-16
- Porsche Cayman S / GTS 3.4L 981 2013-16

Pipe from the right side radiator to the center mounted radiator

Fits:
Porsche 987.1 Boxster 2005-08 Tiptronic transmission
Porsche 987.2 Boxster 2009-12
Porsche 987C.1 Cayman 2005-08 Tiptronic transmission
Porsche 987C.2 Cayman 2009-12
Porsche 997.1 Carrera 2005-08 Tiptronic transmission
Porsche 997.2 Carrera 2009-12
Click 'Zoom in' for large parts diagram.
Diagram ref no 11
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99710663804
The product you are viewing cross references to these numbers
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche Boxster 987 MKII 2.9L 2009-2012
- Porsche Boxster S 987 MKII 3.4L 2009-2012
- Porsche 997 MK1 Carrera 2 3.6L 2005-08
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4 3.6L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08
- Porsche 997 MKII Carrera C2 3.6L 2009-12
- Porsche 997 MKII Carrera C4 3.6L 2009-12
- Porsche 997 MKII Carrera C2S 3.8L 2009-12
- Porsche 997 MKII Carrera C4S 3.8L 2009-12
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
- Porsche Cayman 2.9L 987C MKII 2009-12
- Porsche Cayman S / R 3.4L 987C MKII 2009-12

Fits:
Porsche 996 C2 / C4 1998-05
Porsche 986 Boxster S 3.2L 1997-04
This product supersedes Porsche's old part numbers:
- 99610662554
- 99610662557
Click 'Zoom in' for large parts diagram.
Diagram Ref No 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610662558
The product you are viewing cross references to these numbers
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster S 986 3.2L 2003-04
- 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


Fits:
Porsche 996 C2 / C4 1998-05
Porsche 986 Boxster S 3.2L 1997-04
This product supersedes Porsche's old part numbers:
- 99610662554
- 99610662557
Click 'Zoom in' for large parts diagram.
Diagram ref no 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610662558
The product you are viewing cross references to these numbers
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster S 986 3.2L 2003-04
- 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

Fits:
Porsche 986 Boxster 2.5L / 2.7L 1997-04 (NOT 3.2L S)
This product supersedes Porsche's old part numbers:
- 99610662501
Click picture for large parts diagram.
Diagram Ref No 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610662504
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster 986 2.7L 2003-04


Fits:
Porsche 986 Boxster 2.5L / 2.7L 1997-04 (NOT 3.2L S)
This product supersedes Porsche's old part numbers:
- 99610662600
- 99610662601
Click 'Zoom in' for large parts diagram.
Diagram ref no 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610662603
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster 986 2.7L 2003-04


Fits:
Porsche 996 C2 / C4 1998-05 TIPTRONIC
Porsche 996 C4S 1998-05 TIPTRONIC
Porsche 996 GT3 1998-05
Porsche 986 Boxster S 3.2L 1997-04
This product supersedes Porsche's old part numbers:
- 99610666651
- 99610666652
- 99610666655
Click 'Zoom in' for large parts diagram.
Diagram Ref No 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610666656
The product you are viewing cross references to these numbers
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster S 986 3.2L 2003-04
- 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 GT3 MKI 1999-02
- Porsche 996 GT3 MKII 2003>>

Fits:
Porsche 996 C2 / C4 1998-05 TIPTRONIC
Porsche 996 C4S 1998-05 TIPTRONIC
Porsche 996 GT3 1998-05
Porsche 986 Boxster S 3.2L 1997-04
This product supersedes Porsche's old part numbers:
- 99610666651
- 99610666652
- 99610666655
Click 'Zoom in' for large parts diagram.
Diagram Ref No 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610666656
The product you are viewing cross references to these numbers
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster S 986 3.2L 2003-04
- 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 GT3 MKI 1999-02
- Porsche 996 GT3 MKII 2003>>

Fits:
Porsche 986 Boxster 2.5L / 2.7L 1997-04 (NOT 3.2L S)
This product supersedes Porsche's old part numbers:
- 99610662600
- 99610662601
Click 'Zoom in' for large parts diagram.
Diagram ref no 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610662603
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster 986 2.7L 2003-04

Fits:
Porsche 986 Boxster 2.5L / 2.7L 1997-04 (NOT 3.2L S) MANUAL
This product supersedes Porsche's old part numbers:
- 99610662101
Click 'Zoom in' for large parts diagram.
Diagram Ref No 8.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610662102
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster 986 2.7L 2003-04

Fits:
Porsche 996 C2 / C4 1998-05 MANUAL (NOT C4S)
This product supersedes Porsche's old part numbers:
- 99610662157
Click 'Zoom in' for large parts diagram.
Diagram ref no 8.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610662158
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- 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


Fits:
Porsche 986 Boxster 2.5L / 2.7L 1997-04 (NOT 3.2L S) MANUAL
This product supersedes Porsche's old part numbers:
- 99610662101
Click 'Zoom in' for large parts diagram.
Diagram Ref No 8.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610662102
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster 986 2.7L 2003-04


Fits:
Porsche 996 C2 / C4 1998-05 TIPTRONIC
Porsche 986 Boxster 2.5L / 2.7L 1997-04 TIPTRONIC
Porsche 986 Boxster S 3.2L
This product supersedes Porsche's old part numbers:
- 99610666555
- 99610666557
Click picture for large parts diagram.
Diagram Ref No 8.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610666558
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- 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
Radiator Section Coolant Hoses – Mid & Rear-Engine Porsche Models
Radiator section coolant hoses are essential for managing engine temperature in mid and rear-engine Porsche models. These hoses circulate coolant between the engine and the radiator, ensuring consistent temperature control and preventing overheating under high-performance conditions.
At Design911, we stock a full range of genuine and manufacturer-quality radiator section coolant hoses specifically designed for mid- and rear-engine Porsche models such as the 911, Boxster, and Cayman. Each hose is built to factory specifications for perfect fitment, superior pressure tolerance, and reliable cooling system performance — ensuring your Porsche operates safely and efficiently on road or track.
What Do Radiator Section Coolant Hoses Do?
In Porsche’s mid- and rear-engine designs, coolant must
travel a greater distance between the engine (located at the rear or middle)
and the radiator (at the front). The radiator section hoses form part of
this vital network, helping to:
- Transport
coolant efficiently from the engine to the front radiator.
- Maintain
optimal engine operating temperature for performance and longevity.
- Regulate
coolant flow through the entire system under varying loads.
- Ensure consistent pressure and leak-free circulation.
These hoses are engineered to handle high thermal and mechanical stress, ensuring reliability even in extreme driving conditions.
Why Do Radiator Coolant Hoses Fail?
Due to their exposure to heat, pressure, and constant
coolant flow, radiator section hoses can wear out over time. Common causes of
failure include:
- Material
fatigue from heat cycles and pressure changes.
- Cracks
or splits in aging rubber or plastic connectors.
- Corrosion
or leaks around hose clamps and fittings.
- Swelling
or softening from prolonged coolant exposure.
- Abrasion damage from rubbing against engine or chassis parts.
Symptoms of a failing coolant hose may include coolant leaks under the car, overheating, fluctuating temperature readings, or a low coolant warning light.
Why Replace Faulty Radiator Section Hoses?
A worn or leaking hose can cause coolant loss, overheating, and potential engine damage. Replacing aging hoses is an essential part of preventative maintenance — especially in mid- and rear-engine Porsche models, where efficient cooling is critical.
Benefits of replacement include:
- Restored, leak-free coolant circulation.
- Improved temperature control and system pressure.
- Prevention of costly overheating and engine damage.
- Manufacturer-quality materials for long-term reliability.
All replacement hoses in this range are constructed using reinforced, high-performance rubber compounds and precision-moulded fittings, ensuring durability, flexibility, and perfect compatibility with Porsche cooling systems.