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 And Thermostat Kit
Water Pump And Thermostat Kit
Packaged by Turner - Corporate Logo
T#:5376274
Part#: 11517586925TKT
In Stock
Sale - Save 25% $ 448.99

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

$ 337.56 USD
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Sale - Save 25%
$ 448.99

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

$ 337.56 USD
Free Shipping
Add to Wish List
Everything you need to replace your water pump and thermostat. The water pumps in these BMW models are known for failure near 80,000 miles is a very common issue often times leaving the owner stranded. The aftermarket kit offered provides a single stop for water pump and thermostat replacement needs to save the search and get you back on the road. Kit includes: Mahle-Behr thermostat Water pump Genuine BMW coolant thermostat to water pump hose Mounting hardware required for both the thermostat and water pump
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Complete Cooling System Overhaul Package - 2003-4/2004 Z4 2.5 3.0
Complete Cooling System Overhaul Package - 2003-4/2004 Z4 2.5 3.0 ...
Packaged by Turner - Corporate Logo
T#:339100
Part#: TMS224320
In Stock at Vendor
Starting at $ 514.24 USD
Free Shipping
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Starting at $ 514.24 USD
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This is a customizable cooling system overhaul kit, which starts off with the basic radiator and water pump and can be configured to replace all the M54 common cooling system failure parts in one package. This cooling system package is for the 2003-2005 Z4 Roadster.

The Z4 cooling system is much like that of the sister 3 series. Several of the primary cooling components are prone to failure within 60k miles (or less in many cases). A failure in the cooling system can lead to overheating and catastrophic engine failure. Don't gamble your engine! By replacing these core items preventatively, such as the radiator & waterpump, you are defusing what could be a ticking cooling system time bomb. And if you've had a failure of one of these parts, now is the time to refresh your cooling system. Available with our kit is an OEM Behr radiator, an Original BMW water pump (with updated composite impeller), thermostat (complete with housing), radiator cap, new hoses, and other essential cooling parts.

Optional items (which can be added below):
  • Radiator cap
  • Major cooling hoses
  • Original BMW antifreeze
  • Upgrade the water pump to a Stewart EMP High Performance pump
  • Add a new coolant expansion tank (known for cracking)
  • Include a new coolant level sensor (known for failing / throwing "check coolant" messages)
  • Include a new coolant temp sensor (located in the lower radiator hose) (re-using the old sensor and seal may lead to a leak)
  • Add a new thermostat for an automatic transmission (located with the expansion tank).
    This cooling system overhaul kit fits the following BMWs:
    2003-2005 E85 BMW Z4 2.5i Z4 3.0i

    Please put a check in the boxes next to the items you wish to order.
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    Thermostat Replacement Kit - E39 E46 E60 E53 Z3 Z4 With M54, M52TU Engine
    Thermostat Replacement Kit - E39 E46 E60 E53 Z3 Z4 With M54, M52TU En...
    Packaged by Turner - Corporate Logo
    T#:554073
    Part#: 11537509227KT3
    Ships on Jan 14, 2027
    $ 101.99 USD
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    $ 101.99 USD
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    When it comes time to replace your thermostat, be sure you have everything you need. This kit includes everything you need to replace your thermostat, including the thermostat.

    Kit includes:

    • Mahle-Behr thermostat with gasket
    • Thermostat mounting hardware
    • 1 liter of coolant

    Applications:
    1999-2003 E39 528i, 525i, 530i sedan, touring wagon (M52TU engine, M54 engine)
    1999-2005 E46 323, 328, 325, 330 sedan, coupe, cabrio, touring wagon (M52TU engine, M54 engine)
    2004-2005 E60 525i, 530i sedan, touring wagon (M54 engine)
    2001-2006 E53 X5 3.0 (M54 engine)
    2004-2006 E83 X3 2.5i X3 3.0i (M54 engine)
    1999-2002 Z3 2.3. Z3 2.5i, 2.8 Z3 3.0i (M54 engine)
    2003-2005 Z4 2.5i, Z4 3.0 (M54 engine)

     

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    Complete Cooling System Overhaul Package - 4/2004-2005 Z4 2.5 3.0
    Complete Cooling System Overhaul Package - 4/2004-2005 Z4 2.5 3.0 ...
    Packaged by Turner - Corporate Logo
    T#:339099
    Part#: TMS16430
    In Stock at Vendor
    Starting at $ 514.24 USD
    Free Shipping
    Add to Wish List
    Starting at $ 514.24 USD
    Free Shipping
    Add to Wish List
    This is a customizable cooling system overhaul kit, which starts off with the basic radiator and water pump and can be configured to replace all the M54 common cooling system failure parts in one package. This cooling system package is for the 2003-2005 Z4 Roadster.

    The Z4 cooling system is much like that of the sister 3 series. Several of the primary cooling components are prone to failure within 60k miles (or less in many cases). A failure in the cooling system can lead to overheating and catastrophic engine failure. Don't gamble your engine! By replacing these core items preventatively, such as the radiator & waterpump, you are defusing what could be a ticking cooling system time bomb. And if you've had a failure of one of these parts, now is the time to refresh your cooling system. Available with our kit is an OEM Behr radiator, an Original BMW water pump (with updated composite impeller), thermostat (complete with housing), radiator cap, new hoses, and other essential cooling parts.

    Optional items (which can be added below):
  • Radiator cap
  • Major cooling hoses
  • Original BMW antifreeze
  • Upgrade the water pump to a Stewart EMP High Performance pump
  • Add a new coolant expansion tank (known for cracking)
  • Include a new coolant level sensor (known for failing / throwing "check coolant" messages)
  • Include a new coolant temp sensor (located in the lower radiator hose) (re-using the old sensor and seal may lead to a leak)
  • Add a new thermostat for an automatic transmission (located with the expansion tank).
    This cooling system overhaul kit fits the following BMWs:
    4/2004-2005 E85 BMW Z4 2.5i Z4 3.0i

    Please put a check in the boxes next to the items you wish to order.
    • Show More Show Less
    CSF OE Style Radiator - E85/86 Z4 M, E46 Non-M (Automatic Transmission)
    CSF OE Style Radiator - E85/86 Z4 M, E46 Non-M (Automatic Transmissio...
    2X Entries For Our G87 M2 Sweepstakes!
    CSF - Corporate Logo
    T#:582698
    Part#: 3709
    In Stock
    $ 110.99 USD
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    $ 110.99 USD
    Free Shipping
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    This is a factory original style radiator from CSF and will fit perfectly into the stock location. Cooling will be identical to what your car came with originally. A great replacement with all the proper connections and in all of the proper locations.
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    OEM Nissens Radiator - Automatic - E46, Z4
    OEM Nissens Radiator - Automatic - E46, Z4
    Nissens - Corporate Logo
    T#:362222
    Part#: 17119071519
    In Stock
    $ 173.39

    This product was last offered at the strikethrough price on
    06-02-2026

    $ 165.05 USD
    Free Shipping
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    $ 165.05 USD
    Free Shipping
    Add to Wish List

    The cooling system is a weak point on any E46. Many cars develop issues in as few as 50,000 miles.

    Overheating an inline 6 engine almost always results in large repair bill, and sometimes a warped cylinder head.

    Replace yours with a high-quality OEM Nissens radiator to prevent further issues and potential overheating.

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