BMW Cooling System Parts & Accessories for BMW Z Series E85/6 (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 Nov 17, 2026
New Item
$ 990.99

This product was last offered at the strikethrough price on
06-22-2026

$ 954.99 USD
Free Shipping on orders $49 and up
$ 954.99 USD
Free Shipping on orders $49 and up
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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Mishimoto Water Pump - BMW M50, M52, M54, S50, S52
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Mishimoto - Corporate Logo
T#:51075091
Part#: MMWP-M50-92
In Stock
New Item
$ 72.99 USD
Free Shipping on orders $49 and up
The Mishimoto Performance Water Pump provides the thermal stability required for modified engines.
ECS High-Flow Water Pump Upgrade - E9X E8X N52
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
ECS - Corporate Logo
T#:49822518
Part#: 044952LA04KT
Ships on Aug 11, 2026
New Item
Sale - Save 25% $ 477.99

This product was last offered at the strikethrough price on
06-14-2026

$ 358.49 USD
Free Shipping
Sale - Save 25%
$ 477.99

This product was last offered at the strikethrough price on
06-14-2026

$ 358.49 USD
Free Shipping

The N5X family of engines marked the start of a new era for BMW. The all-new aluminum block powerplants featured a host of technical upgrades, aiding in power output, reliability, and performance. Among these technological advances is an external electronic water pump, which removed load from the engine's accessory drive and allowed for advanced pulse-width-modulated (PWM) control.

From factory, the N52's electronic water pump is limited to a measly 200W output—strong enough for daily driving, but lacking in performance applications. Recognizing this shortcoming, ECS engineers set out to create a high-flow water pump upgrade that doesn't break the bank. Their high-quality adapter wiring harness and bracket allow you to install a 400W N54 water pump without any modification, an effortless, yet effective upgrade that doubles the output of the factory water pump!

By increasing coolant flow capacity, the 400W pump improves heat extraction from the cylinder head and engine block during high-load operation. This added thermal headroom is particularly beneficial for modified engines, sustained aggressive driving, track use, or operation in elevated ambient temperatures where the factory pump can operate near its limits. Improved circulation helps maintain more stable coolant temperatures and reduces the risk of localized hot spots.

Features & Benefits:

Upgrades to the more powerful 400W N54 water pump for increased coolant flow and improved engine cooling efficiency Sealed adaptor harness ensures secure connections and optimal operation under demanding conditions The N54 pump's higher power output offers longer-lasting, more effective cooling compared to the stock N52 pump Design:

40A fused power wire safely handles the increased power demands of the N54 pump, providing consistent and stable performance Sealed and robust construction, designed to withstand heat and moisture, ensuring reliability in even the most challenging environments Plug-and-play compatibility is designed for easy integration with the N52 engine and N54 water pump, minimizing installation time and complexity Kit Contents:

ECS N54 Water Pump Adapter Kit Conversion wiring harness Aluminum bracket Installation hardware Bavarian Autosport Water Pump (11517632426)

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Water Connector - Expansion Tank To Trans Oil Cooler - E83 Z4 ...
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
URO - Corporate Logo
T#:50031879
Part#: 17112248409
Ships in 1 Business Day
New Item
$ 40.99 USD
Free Shipping on orders $49 and up
Plastic cooling system components degrade and become brittle with age and heat exposure. This particular part is especially prone to damage during expansion tank removal. Always inspect it whenever the expansion tank is removed and replace it if any cracking or wear is found.
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Hex Bolt & Washer Kit
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Genuine BMW - Corporate Logo
T#:55245856
Part#: 0711990XXKTKT
Ships in 5 Business Days
New Item
$ 26.83 USD
Free Shipping on orders $49 and up
Turner Motorsport offers this Genuine BMW Hex Bolt and Washer Kit to keep your chassis maintenance or engine refresh completely up to factory standard.
ECS High-Flow Water Pump Upgrade With Aluminum Water Pump - E9X E8X N...
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
ECS - Corporate Logo
T#:49822519
Part#: 044952LA04AKT
In Stock
New Item
$ 597.99 USD
Free Shipping
$ 597.99 USD
Free Shipping

The N5X family of engines marked the start of a new era for BMW. The all-new aluminum block powerplants featured a host of technical upgrades, aiding in power output, reliability, and performance. Among these technological advances is an external electronic water pump, which removed load from the engine's accessory drive and allowed for advanced pulse-width-modulated (PWM) control.

From factory, the N52's electronic water pump is limited to a measly 200W output—strong enough for daily driving, but lacking in performance applications. Recognizing this shortcoming, ECS engineers set out to create a high-flow water pump upgrade that doesn't break the bank. Their high-quality adapter wiring harness and bracket allow you to install a 400W N54 water pump without any modification, an effortless, yet effective upgrade that doubles the output of the factory water pump!

By increasing coolant flow capacity, the 400W pump improves heat extraction from the cylinder head and engine block during high-load operation. This added thermal headroom is particularly beneficial for modified engines, sustained aggressive driving, track use, or operation in elevated ambient temperatures where the factory pump can operate near its limits. Improved circulation helps maintain more stable coolant temperatures and reduces the risk of localized hot spots.

Features & Benefits:

Upgrades to the more powerful 400W N54 water pump for increased coolant flow and improved engine cooling efficiency Sealed adaptor harness ensures secure connections and optimal operation under demanding conditions The N54 pump's higher power output offers longer-lasting, more effective cooling compared to the stock N52 pump Design:

40A fused power wire safely handles the increased power demands of the N54 pump, providing consistent and stable performance Sealed and robust construction, designed to withstand heat and moisture, ensuring reliability in even the most challenging environments Plug-and-play compatibility is designed for easy integration with the N52 engine and N54 water pump, minimizing installation time and complexity Kit Contents:

ECS N54 Water Pump Adapter Kit Conversion wiring harness Aluminum bracket Installation hardware Pierburg Full Aluminum Water Pump (11515A05704) Installation:

- Click HERE for Installation Instructions -

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Water Pump Installation Hardware Kit
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Genuine BMW - Corporate Logo
T#:55209926
Part#: 0071199KT
In Stock
New Item
$ 7.94 USD
Free Shipping on orders $49 and up
This Genuine BMW water pump installation hardware kit is the exact factory refresh package needed to maintain the structural integrity of your cooling system's plumbing.
CSF Universal Large Single-Pass Oil Cooler - Universal Application ...
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Universal fitment design - modifications may be necessary to run this cooler
CSF - Corporate Logo
T#:53608839
Part#: 8371
Ships in 3 Business Days
New Item
$ 499.00 USD
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$ 499.00 USD
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CSF redesigned this cooler and went with a more traditional inlet/outlet orientation. The new single pass design features high efficiency and high durability, but with vertically oriented inlet and outlet connections.
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Gneuine BMW Water Pump & Thermostat Kit - BMW Z3 Z4 S54 3.2L ...
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Genuine BMW - Corporate Logo
T#:48194754
Part#: ZS54WPTKT
Ships in 5 Business Days
New Item
$ 1,152.99 USD
Free Shipping on orders $49 and up
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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Oil Cooler Line O-Ring & Screw Kit
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Genuine BMW - Corporate Logo
T#:55281750
Part#: 1722OCLKT
Ships in 2 Business Days
New Item
$ 20.60 USD
Free Shipping on orders $49 and up
This Genuine BMW Oil Cooler Line O-Ring & Screw Kit includes the exact factory components required to safely service your oil cooler hard lines.
Coolant Thermostat
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Meyle - Corporate Logo
T#:55461389
Part#: 11537549476
Special Order: No Guaranteed ETA
New Item
$ 81.99 USD
Free Shipping on orders $49 and up
This Meyle coolant thermostat provides a refresh for your thermal management system, keeping your engine operating exactly where the engineers intended.
Electric Water Pump
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Meyle - Corporate Logo
T#:54959290
Part#: 313 220 0017
Special Order: No Guaranteed ETA
New Item
$ 326.99 USD
Free Shipping on orders $49 and up
Whether you are daily driving or doing a preventative cooling overhaul, this high-quality replacement pump includes fresh mounting hardware to ensure your BMW's cooling system remains reliable.