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Bremmen Parts BMW Cooling System Parts & Accessories

The cooling system is arguably the weakest point in numerous BMWs. If you drive an aging BMW or plan on taking your car to the track like we do, we recommend beefing up your cooling system before going to the track. Generally, the main components in your cooling system that are prone to failure include the following: expansion tank, factory hoses, water pump, thermostat, fan (especially if your vehicle comes factory with a clutch fan), and radiator. Factory BMW expansion tanks are plastic and prone to either breaking off at connection points or combusting. As factory rubber hoses age they either crack or break over time - we offer silicone cooling hose upgrades for most applications to avoid future failures. If you have an older vehicle, your water pump likely comes from the factory with a plastic impeller - we offer upgraded water pumps with metal impellers that are far more reliable. Newer model BMWs utilize electric water pumps - BMW spent millions of dollars engineering these water pumps, but they fail so often that we recommend replacing at 60,000 mile service intervals to avoid being stranded on the side of the road. In terms of thermostats, we offer various upgraded thermostats for racing applications. If your BMW utilizes a clutch fan from the factory, we have several options available in terms of universal electric fans - we recommend replacing these to avoid sending brittle plastic fan blades through your hood. For radiators, we recommend swapping out your radiator for one that does not use plastic connection points like your factory radiator.

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Thermostat With Aluminum Housing - N20

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T#:30828065

Part#: 11538635689M

In Stock

Sale - Save 20% $ 125.99

This product was last offered at the strikethrough price on
05-03-2026

$ 100.36 USD

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Sale - Save 20%

$ 125.99

This product was last offered at the strikethrough price on
05-03-2026

$ 100.36 USD

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Bav Auto Radiator Hose - Lower - E46 M52 M54

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T#:640203

Part#: 11531436408

In Stock

Sale - Save 16% $ 36.99

This product was last offered at the strikethrough price on
05-03-2026

$ 31.20 USD

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Sale - Save 16%

$ 36.99

This product was last offered at the strikethrough price on
05-03-2026

$ 31.20 USD

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OEM Replacement Lower Radiator Hose for E46 3 series (Non-M3). We recommend replacing the Coolant Temperature Sensor while replacing this hose as the original sensor is often damaged while trying to remove it from the old hose. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.

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Bav Auto Coolant Expansion Tank - E53 X5, Z3 2.3 2.5i 2.8 3.0i ...

affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

T#:640497

Part#: 17107514964

Ships in 8 Business Days

Sale - Save 16% $ 63.99

This product was last offered at the strikethrough price on
05-03-2026

$ 53.75 USD

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Qty

Sale - Save 16%

$ 63.99

This product was last offered at the strikethrough price on
05-03-2026

$ 53.75 USD

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This radiator expansion tank is used on E53 X5 4.4i and 4.6is with M62 engine, and Z3 2.3 2.5i 2.8 3.0i from 1999-2002. It is a common failure item as the plastic weakens over time and stress cracks will lead to coolant leaks. We have found that the expansion tanks should be replaced based on age as well as condition. Expansion tanks seem to have a lifespan of less than six years before they show signs of fatigue and wear. Pre-emptively replacing the expansion tank as part of an overall maintenance plan can prevent you from getting stranded from a sudden failure later on. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.

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Bremmen Parts BMW Cooling System Parts & Accessories

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Thermostat With Aluminum Housing - N20

Bav Auto Radiator Hose - Lower - E46 M52 M54

Bav Auto Coolant Expansion Tank - E53 X5, Z3 2.3 2.5i 2.8 3.0i ...

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