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Genuine BMW BMW Cooling System Parts & Accessories for BMW E46 M3 S54 (1999-2005)

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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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Genuine BMW Coolant Expansion Tank - E46 M3

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T#:13185

Part#: 17112283344

In Stock

7% off MSRP $ 215.23

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 199.98 USD

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7% off MSRP

$ 215.23

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 199.98 USD

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This radiator coolant reservoir/expansion tank for E46 M3 is a common failure item as the plastic weakens over time and stress crack will lead to coolant leaks. If your car has over 80k miles and hasn't had one of these replaced, we highly recommend it during your next major service. We have found that the aftermarket coolant reservoirs fail easier than the original BMW piece so we only offer the BMW type on this part.

When doing any sort of repair or maintenance there is no replacement for genuine factory parts. Turner Motorsport carries the Genuine BMW brand with pride and has the parts you need to complete your next project with confidence.

This item fits the following BMWs:
2001-2006 E46 BMW M3

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Expansion Tank Water Pipe / Connecting Hose - E46 M3

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T#:12482

Part#: 17112229053

In Stock

1% off MSRP $ 96.35

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 95.28 USD

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1% off MSRP

$ 96.35

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 95.28 USD

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This is the Genuine BMW coolant reservoir / expansion tank vent hose for E46 M3 with the S54 engine.

This item fits the following BMWs:
2001-2006 E46 BMW M3

Genuine BMW Thermostat - 80*C - E46 M3, MZ3 S54, Z4 M

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T#:12502

Part#: 11531318274

In Stock

16% off MSRP $ 147.44

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 123.15 USD

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16% off MSRP

$ 147.44

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 123.15 USD

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GENUINE BMW THERMOSTAT - E46 M3, MZ3 (S54), MZ4. This is just the thermostat itself and does not include the housing o-ring or any others that are advised for replacement. See thermostat kit or our water pump kit for a complete package.

When doing any sort of repair or maintenance there is no replacement for genuine factory parts. Turner Motorsport carries the Genuine BMW brand with pride and has the parts you need to complete your next project with confidence.

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Thermostat With O-Rings - E46 M3, MZ3, Z4 M

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T#:2303

Part#: 11531318274-K

Ships on Jul 13, 2026

$ 148.76 USD

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$ 148.76 USD

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Replacement stock thermostat for E46 M3, Z3M w S54 engine, Z4M.The thermostat can be replaced on the E46 M3 without removing the water pump. This can save you money if the pump still has life left on it but the thermostat needs to be done now. Symptoms of a bad thermostat include an erratic temp gauge and a fault code. When replacing the thermostat, there are three o-rings that will likely need to be replaced between the thermostat and the water pump housing, and two on the coolant tube going to the head. We also recommend new hoses, clamps, and BMW coolant. Replacement should take about one hour.

Note: even though this can be done without replacing the water pump, the job involves removing the same items to access this area. And opening the thermostat housing will spill a lot of coolant. In other words, if you don't replace the water pump at the same time, you're going to repeat this process when the pump needs replacing. We offer a complete water pump overhaul package that covers everything you need if you want to it all at once. You can the thermostat to that package and get everything without any duplicate parts. Click here for the E46 M3 water pump kit.

On S54 engines (E46 M3, MZ3, Z4 M) there is a flanged head bolt going into the cylinder head, behind the thermostat cover. This holds the left side timing chain guide rail in place and if it's loose or falls out you could have a very serious engine failure to deal with. Make sure to check this bolt while you have the thermostat cover off. You only need to make sure it's tight. But if it's come loose you may want to replace the seal ring and use a small touch of oil-resistant thread sealer.

This item fits the following BMWs:
2000-2001 E46 3 Series M3 M3 Convertible 2000-2006
2001-2002 Z3 Roadster / Coupe Z3 M Roadster Z3 M Coupe w S54 Engine
2006-2008 E86 E86 Z4 Z4 M Roadster Z4 M Coupe

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Genuine BMW Fan Blade

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T#:360662

Part#: 11521712058

Ships on Jan 4, 2027

6% off MSRP $ 104.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 98.99 USD

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6% off MSRP

$ 104.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 98.99 USD

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Genuine BMW Coolant Pipe - E46 M3

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T#:13013

Part#: 11537830711

In Stock

Sale - Save 5% $ 154.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 147.10 USD

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Sale - Save 5%

$ 154.99

This product was last offered at the strikethrough price on
06-25-2026

$ 147.10 USD

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Genuine BMW Pipe
This item fits the following BMW Chassis:
E46 M3,E46

Fits BMW Engines including:
S54

Genuine BMW Radiator Hose - Upper - E46 M3

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T#:360696

Part#: 11537830716

Ships in 2 Business Days

$ 65.99 USD

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$ 65.99 USD

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Genuine BMW Radiator Hose - Lower - E46 M3 S54 3.2L

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T#:360695

Part#: 11537830715

Ships in 2 Business Days

$ 64.99 USD

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$ 64.99 USD

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Genuine BMW Radiator Fan Clutch

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T#:367654

Part#: 11527831619

Ships in 2 Business Days

3% off MSRP $ 401.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 388.99 USD

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3% off MSRP

$ 401.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 388.99 USD

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Ensure optimal engine cooling for your BMW with this Fan Clutch, designed to adapt the fan speed based on the engine's rotational speed. Perfect for city driving and traffic, this fan clutch minimizes rotational load and drag when cooling is not critical.

Compatible with various BMW models
Adjusts fan speed based on engine rotational speed
Ideal for city driving and traffic conditions
Reduces rotational load and drag when cooling is not critical
Enhances engine cooling efficiency
Suitable for vehicles with mechanical fans
Easy solution for vehicles running hot in traffic

Upgrade your BMW's cooling system with this Fan Clutch, ensuring a cool and efficient engine performance, especially during city driving and traffic stops.

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Genuine BMW Water Pipe - Thermostat Housing to Return Pipe - E46 Z3 Z...

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T#:36149

Part#: 11537830710

Ships in 5 Business Days

4% off MSRP $ 76.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 73.99 USD

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4% off MSRP

$ 76.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 73.99 USD

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Genuine BMW Pipe
This item fits the following BMW Chassis:
E46 M3,E85 Z4M,E46,E85 Z4,E86 Z4

Fits BMW Engines including:
S54

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