BMW Cooling System Parts & Accessories for BMW Z4 M Roadster S54 (2003-2008)

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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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Water Pump & Thermostat Kit - BMW Z3 Z4 S54 3.2L
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Packaged by Turner - Corporate Logo
T#:48194755
Part#: ZS54WPTKT2
Ships on Dec 18, 2026
$ 1,022.99

This product was last offered at the strikethrough price on
07-16-2026

$ 970.99 USD
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$ 970.99 USD
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It is important that your coolant system is serviced at regular intervals to ensure a long life. Over time, coolant systems are exposed to high temperatures and repeated thermal cycling, which causes warping, cracking, and hardening of plastics and rubber components in the coolant system. This can lead to coolant leaks and overheating, which can result in extensive engine damage if not resolved in a timely manner. This Water Pump & Thermostat kit helps to address a few of the most problematic parts, replacing these items entirely to keep your cooling system running optimally and efficiently.
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Rein Coolant Bleeder Screw CHW1575 - Priced Each
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:591955
Part#: 17111712788
In Stock
Sale - Save 22% $ 4.99

This product was last offered at the strikethrough price on
08-31-2026

$ 3.87 USD
Free Shipping on orders $49 and up
Sale - Save 22%
$ 4.99

This product was last offered at the strikethrough price on
08-31-2026

$ 3.87 USD
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Coolant Bleeder Screw is a critical component for maintaining your BMW’s cooling system. Designed to release trapped air from the coolant lines, this screw ensures efficient coolant flow and prevents overheating. Specifically engineered for BMW models, it enhances the overall performance and longevity of your engine by maintaining proper temperature regulation. Comes with O-Ring.
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Meyle Expansion Tank Cap
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We Price Match - Give Us A Call or Chat!
Meyle - Corporate Logo
T#:579357
Part#: 3148009004
In Stock
Sale - Save 40% $ 14.99

This product was last offered at the strikethrough price on
05-15-2026

$ 8.99 USD
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Sale - Save 40%
$ 14.99

This product was last offered at the strikethrough price on
05-15-2026

$ 8.99 USD
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Replace worn or missing pieces.

Aluminum Screws for N52 N54 Water Pump
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Rein - Corporate Logo
T#:2253
Part#: 11510392553
In Stock
Sale - Save 5% $ 7.13

This product was last offered at the strikethrough price on
08-31-2026

$ 6.77 USD
Free Shipping on orders $49 and up
Sale - Save 5%
$ 7.13

This product was last offered at the strikethrough price on
08-31-2026

$ 6.77 USD
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These aluminum water pump screws are single use and must be replaced each time they are removed. These are used on all 325i, 328i, and 330i with the BMW N51 N52 and N53 engines. They were also used on some early N54 engines that have rubber mounts on the water pump housing. Do not use these bolts if your N54 water pump has been replaced with a housing that does not have the rubber mounts.

In German, Rein means Pure. In the automotive industry the Rein name has quickly come to represent quality. With fitments for some of the world’s finest automobiles including BMW and Mini and guaranteed OE quality, Rein is a name you can trust.

This item fits the following BMWs:
2008+ E82 BMW 128i 135i
2007+ E9X BMW 325i 325xi 328i 328xi 330i 335i 335xi
2006+ E60 BMW 525i 525xi 528i 528xi 530i 530xi 535i 535xi
2006+ X3 BMW X3 3.0i X3 3.0si
2006+ Z4 BMW Z4 3.0i Z4 3.0si
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Bavarian Autosport - Corporate Logo
T#:640208
Part#: 17117639022
In Stock
Sale - Save 15% $ 13.99

This product was last offered at the strikethrough price on
06-03-2026

$ 11.89 USD
Free Shipping on orders $49 and up
Sale - Save 15%
$ 13.99

This product was last offered at the strikethrough price on
06-03-2026

$ 11.89 USD
Free Shipping on orders $49 and up
This radiator expansion tank cap is used most BMW's from 1991-2006. It is a common failure item. When this item fails, it cannot hold pressure which results in your BMW overheating. If you are overhauling your coolant system, now is the time to consider preventative replacing this cap. It is also referred to as the coolant reservoir cap. 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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Rein - Corporate Logo
T#:340541
Part#: 17111742231
Ships in 2 Business Days
Sale - Save 5% $ 17.99

This product was last offered at the strikethrough price on
08-31-2026

$ 17.09 USD
Free Shipping on orders $49 and up
Sale - Save 5%
$ 17.99

This product was last offered at the strikethrough price on
08-31-2026

$ 17.09 USD
Free Shipping on orders $49 and up
This radiator expansion tank cap is used most BMW's from 1991-2006. It is a common failure item. When this item fails, it cannot hold pressure which results in your BMW overheating. If you are overhauling your coolant system, now is the time to consider preventative replacing this cap. It is also referred to as the coolant reservoir cap.
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Bav Auto Temperature Sensor - BMW E39 E46 E9X E60 F01/02
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:639833
Part#: 13621433076
In Stock
Sale - Save 20% $ 14.99

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

$ 11.99 USD
Free Shipping on orders $49 and up
Sale - Save 20%
$ 14.99

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

$ 11.99 USD
Free Shipping on orders $49 and up
This is the coolant temperature sensor used in many BMW models from the late-1990s to the mid-2010s. The engine computer relies on the coolant temp to set the fuel mapping for the engine. As the car warms up the computer changes the fuel mixture. If your car is running a bit rich (too much fuel) it could be because this sensor is failing and not sending the correct info to the computer. This sensor is located in a variety of places depending on the engine. But it's one of those easy replacement items 'while you're in there' when doing a water pump or thermostat replacement. 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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Fluid Level Sensor
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We Price Match - Give Us A Call or Chat!
Meyle - Corporate Logo
T#:5973204
Part#: 17117546548
Ships on Sep 21, 2026
$ 13.99 USD
Free Shipping on orders $49 and up
MEYLE-ORIGINAL: True to OE fluid level sensor. Used in multiple locations. Wulf Gaertner Autoparts AG manufactures and markets automotive spare parts under its MEYLE brand. Since its foundation in 1958, Wulf Gaertner Autoparts has been an owner-operated, unlisted family business on the aftermarket scene. Since 1995, Wulf Gaertner Autoparts AG has been manufacturing and trading under its MEYLE brand. They pride themselves on top-grade quality-tested spare parts for passenger cars, vans and commercial vehicles. Comparable OE Cross Reference - 17117546548
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Radiator Support Bracket
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:14122755
Part#: 17117514402
Back Ordered
Sale - Save 13% $ 8.99

This product was last offered at the strikethrough price on
08-13-2026

$ 7.83 USD
Free Shipping on orders $49 and up
Sale - Save 13%
$ 8.99

This product was last offered at the strikethrough price on
08-13-2026

$ 7.83 USD
Free Shipping on orders $49 and up
Mounts to top of radiator bracket, 2 per vehicle.

Meistersatz - Corporate Logo
T#:379740
Part#: 13621433076
In Stock at Vendor
$ 15.99 USD
Free Shipping on orders $49 and up
Monitors coolant / oil temperature