Mounting Bush LOWER for Radiator. Porsche 981 / 718 Boxster / Spyder / 991  ❭  99110633200

Radiator Lower Mounting Bush
Sold each – 4 required per car

The radiator lower mounting bush 99110633101 is an essential component used to support and isolate the radiator within the cooling system of several modern Porsche models including the 981, 718 Boxster, 718 Cayman and the 991.

Fits:

• Porsche Boxster 981 2.7L 2012-16
• Porsche Boxster 981 S / GTS 3.4L 2012-16
• Porsche Boxster 981 Spyder 3.8L 2016
• Porsche Boxster 718 2.0L Manual (300 Bhp) 2017>>
• Porsche Boxster 718 2.0L PDK (300 Bhp) 2017>>
• Porsche Boxster S 718 2.5L Manual (350 Bhp) 05/2017>>
• Porsche Boxster S 718 2.5L PDK (350 Bhp) 05/2017>>
• Porsche Boxster T 718 2.0L Manual (300 Bhp) 01/2019>>
• Porsche Boxster T 718 2.0L PDK (300 Bhp) 01/2019>>
• Porsche Boxster GTS 718 2.5L Manual (365 Bhp) 05/2017>>
• Porsche Boxster GTS 718 2.5L PDK (365 Bhp) 05/2017>>
• Porsche Boxster GTS 718 4.0L Manual (400 Bhp) 01/2019>>
• Porsche Boxster GTS 718 4.0L PDK (400 Bhp) 01/2019>>
• Porsche Boxster Spyder / Sypder RS 718 4.0L 01/2019>>
• Porsche Boxster 25 Years 718 4.0L Manual (400 Bhp) 01/2020>>
• Porsche Boxster 25 Years 718 4.0L PDK (400 Bhp) 01/2020>>
• Porsche 991.1 Carrera C2 3.4L (350 Bhp) 2012-16
• Porsche 991.1 Carrera C2S / GTS 3.8L (400/430 Bhp) 2012-16
• Porsche 991.1 Carrera C4 3.4L (350 Bhp) 2012-16
• Porsche 991.1 Carrera C4S / GTS 3.8L (400/430 Bhp) 2012-16
• Porsche 991.1 Turbo 3.8L (520 Bhp) 2014-16
• Porsche 991.1 Turbo S 3.8L (560 Bhp) 2014-16
• Porsche 991.1 R 4.0L (500 Bhp) 2016
• Porsche 991.1 GT3 3.8L (475 Bhp) 2014-16
• Porsche 991.2 Carrera 2 3.0L (370 Bhp) 2016-19
• Porsche 991.2 Carrera 2S / GTS 3.0L (420/450 Bhp) 2016-19
• Porsche 991.2 Carrera 4 3.0L (370 Bhp) 2016-19
• Porsche 991.2 Carrera 4S / GTS 3.0L (420/450 Bhp) 2016-19
• Porsche 991.2 Cabriolet 2 3.0L (370 Bhp) 2016-19
• Porsche 991.2 Cabriolet 2S / GTS 3.0L (420/450 Bhp) 2016-19
• Porsche 991.2 Cabriolet 4 3.0L (370 Bhp) 2016-19
• Porsche 991.2 Cabriolet 4S / GTS 3.0L (420/450 Bhp) 2016-19
• Porsche 991.2 Targa 4 3.0L (370 Bhp) 2016-19
• Porsche 991.2 Targa 4S / GTS 3.0L (420/450 Bhp) 2016-19
• Porsche 991.2 Turbo Coupe 3.8L (540 Bhp) 2016-19
• Porsche 991.2 Turbo S Coupe 3.8L (580 Bhp) 2016-19
• Porsche 991.2 Turbo Cabriolet 3.8L (540 Bhp) 2016-19
• Porsche 991.2 Turbo S Cabriolet 3.8L (580 Bhp) 2016-19
• Porsche 991.2 Speedster 4.0L (510Bhp) 2019
• Porsche 991.2 GT3 4.0L (500 Bhp) / GT3 RS 4.0L (520 Bhp) 2017-19
• Porsche 991.2 GT2 RS 3.8L PDK (700 bhp) 2018-19
• Porsche Cayman 2.7L 981 2013-16
• Porsche Cayman S / GTS 3.4L 981 2013-16
• Porsche Cayman GT4 3.8L 2015-16
• Porsche Cayman 718 2.0L Manual (300 Bhp)
• Porsche Cayman 718 2.0L PDK (300 Bhp)
• Porsche Cayman S 718 2.5L Manual (350 Bhp)
• Porsche Cayman S 718 2.5L PDK (350 Bhp)
• Porsche Cayman T 718 2.0L Manual (300 Bhp)
• Porsche Cayman T 718 2.0L PDK (300 Bhp)
• Porsche Cayman GTS 718 2.5L Manual (365 Bhp)
• Porsche Cayman GTS 718 2.5L PDK (365 Bhp)
• Porsche Cayman GTS 718 4.0L Manual (400 Bhp)
• Porsche Cayman GTS 718 4.0L PDK (400 Bhp)
• Porsche Cayman GT4 718 4.0L / GT4 RS 718 4.0L
• Porsche Cayman GT4 Clubsport
• Porsche Cayman GT4 RS Clubsport 2020-2024

Diagram Ref No 23  

Although small, this rubber mounting bush plays an important role in stabilising the radiator assembly while absorbing vibration and movement generated by the engine, road surface and cooling fans.

What This Radiator Mounting Bush Does

The lower radiator mounting bush sits between the radiator and the chassis mounting point. It helps secure the radiator in place while isolating vibration.

This component helps:

• Secure the radiator within the cooling system frame
• Absorb vibration and movement from the engine and road
• Prevent stress damage to the radiator housing
• Maintain proper radiator alignment with cooling ducts and fans

Without these bushes functioning correctly, the radiator may move excessively, leading to premature wear or cooling system issues.

Why Radiator Mounting Bushes Fail

Over time, rubber components within the engine bay are exposed to heat, moisture and road debris. This can cause the bush material to deteriorate.

Common causes of failure include:

Heat degradation
Continuous exposure to engine bay temperatures can cause rubber to harden and crack.

Compression fatigue
Years of supporting the radiator weight can flatten or weaken the bush.

Oil and coolant contamination
Exposure to fluids may accelerate rubber deterioration.

General ageing
Rubber components naturally degrade over time and lose elasticity.

Symptoms of a Worn Radiator Mount Bush

• Loose or unstable radiator positioning
• Rattling or vibration from the front cooling system area
• Visible cracking or deterioration of the rubber mount
• Radiator sitting lower or misaligned within the mount

Replacing worn mounting bushes restores proper support and reduces unwanted vibration in the cooling system.

Why You May Need to Replace This Part

Protect the Radiator Assembly
A stable radiator prevents stress on coolant connections, hoses and fittings.

Reduce Vibration and Noise
New bushes absorb vibration and prevent rattling from the radiator frame.

Prevent Cooling System Damage
Loose radiators can lead to cracked plastic tanks, hose strain or coolant leaks.

Affordable Preventative Maintenance
Replacing small rubber mounts during cooling system service or radiator replacement helps extend the life of the entire system.