BMW Cooling System Parts & Accessories for BMW 3 Series E46 (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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Bav Auto Thermostat With Aluminum Housing - M52TU M54
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:12544802
Part#: 11531437040
In Stock
Sale - Save 19% $ 104.99

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

$ 84.99 USD
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Sale - Save 19%
$ 104.99

This product was last offered at the strikethrough price on
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$ 84.99 USD
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The plastic thermostat cover in your BMW is a known point of failure. Throughout years of repeated contact with hot coolant, the plastic can crack and cause massive coolant leaks and potential overheating. Eliminate one of the weak links in your cooling system with a replacement aluminum thermostat housing. By installing this aluminum unit, you have no worries as far as plastic housing cracks go
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Bav Auto Coolant Expansion Tank - E53 X5, E46, E83 X3
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:640496
Part#: 17137787039
In Stock
Sale - Save 18% $ 61.99

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

$ 50.99 USD
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Sale - Save 18%
$ 61.99

This product was last offered at the strikethrough price on
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$ 50.99 USD
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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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Engine Fan - 11 Blades, 420mm - Many 6 Cylinders
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:1287
Part#: 11521712058
In Stock
$ 32.19 USD
Free Shipping on orders $49 and up
This fan is driven by the serpentine belt, engaged by the fan clutch. If you have bad motor mounts, it's quite common for the blades of this fan to make contact with the radiator or radiator shroud, essentially self-destructing the fan into many peices. Be sure to get a new fan clutch, while you are replacing this. 
With more than 4,000 European vehicle replacement parts, URO is no stranger to the market. Superior metal stock and extremely strict quality control are at the forefront of URO’s agenda and it shows as they become the OE supplier for more and more car companies every single day.

This fan fits many 6 cylinder BMWs, including the following:

1989-1994 E32 735i/iL
1991-1995 E34 525i, 535i, M5
1992-1999 E36 3 series with 6 cylinder engine (M3, 325, 328, 323)
1997-2002 Z3 2.3, 2.5, 2.8, 3.0, and MZ3 3.2 (S52)
1997-2003 E39 5 series, 525i, 528i, 530i
1999-2000 E46 3 series 323i/Ci, 328i/Ci
2001-2005 E46 3 series WITH AUTOMATIC TRANSMISSION ONLY
2001-2006 E46 M3 (all):
2001-2006 X5 3.0i
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Bavarian Autosport Water Pipe - E46 E39 Z4 Z3 (M52TU, M54)
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:638085
Part#: 11537502525
In Stock
Sale - Save 20% $ 50.99

This product was last offered at the strikethrough price on
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$ 40.79 USD
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Sale - Save 20%
$ 50.99

This product was last offered at the strikethrough price on
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$ 40.79 USD
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This plastic water pipe is positioned directly underneath your intake manifold. Due to its plastic construction, it is notorious for catastrophic failure. Rapid cooling loss and overheating are both direct results of this failure, posing permanent and lasting damage to the engine.

Replace your cracked/broken coolant pipe with this high-quality Bavarian Autosport component to ensure long-term reliability and perfect fitment.

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 Heater Inlet Pipe - E46 E39 E53 E83 E85 Z3
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:638080
Part#: 11531705210
In Stock
Sale - Save 20% $ 40.99

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

$ 32.79 USD
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Sale - Save 20%
$ 40.99

This product was last offered at the strikethrough price on
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$ 32.79 USD
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This is the plastic heater inlet pipe that connects the cylinder head to the heater inlet on cars with the M52 or M54 engine. The plastic on this hose becomes brittle over time and eventually leads to failure. Replace yours with a brand new Bav Auto Heater inlet pipe to prevent catastrophic failure.
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Bav Auto Expansion Tank Mounting Plate - E46 Non-M w/ Manual Trans ...
For vehicles with a manual transmission only
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:638088
Part#: 17111436250
In Stock
Sale - Save 20% $ 44.99

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

$ 35.99 USD
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Sale - Save 20%
$ 44.99

This product was last offered at the strikethrough price on
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$ 35.99 USD
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This Bav Auto part is the mounting bracket from the radiator to the expansion tank on an E46 3 series with a Manual Transmission. 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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OEM Rein Upper Radiator Hose - E46 M3
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:2306
Part#: 11537830716
In Stock
$ 33.99

This product was last offered at the strikethrough price on
05-06-2026

$ 22.99 USD
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$ 22.99 USD
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Replace your cracked or leaking radiator hose to prevent further leaks and potentially catastrophic failure. This hose replaces the Upper radiator hose that connects the thermostat housing to the radiator.

This Upper Radiator Hose fits the following BMWs:
2001-2006 E46 3 Series M3, M3 Convertible

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Rein Radiator Hose - Upper - E46
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:379786
Part#: 17127510952
In Stock
$ 25.09

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

$ 24.95 USD
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$ 24.95 USD
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A common source of cooling system failure

Bavarian Autosport Radiator Hose - Upper - E46 M52 M54
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:640204
Part#: 17127510952
In Stock
Sale - Save 21% $ 34.99

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

$ 27.74 USD
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Sale - Save 21%
$ 34.99

This product was last offered at the strikethrough price on
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$ 27.74 USD
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Replacement Upper 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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Heater Inlet Pipe
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:594330
Part#: 11531705210
In Stock
$ 42.39 USD
Free Shipping on orders $49 and up
This is the plastic heater inlet pipe that connects the cylinder head to the heater inlet on cars with the M52 or M54 engine.The plastic on this hose becomes brittle over time and eventually leads to failure.
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BMW M52 M54 Water Pipe
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:594294
Part#: 11537502525
In Stock
$ 55.99 USD
Free Shipping on orders $49 and up

BMW M52 M54 Water Pipe is an essential replacement part designed to ensure long-term reliability and optimal performance for your BMW's cooling system. Engineered to replace cracked or broken coolant pipes, this high-quality water pipe from Turner Motorsport guarantees a perfect fit and dependable service. Investing in this replacement pipe helps prevent overheating and potential engine damage, maintaining your vehicle's performance and longevity.

  • Reliable replacement: Designed to replace cracked or broken coolant pipes for improved engine cooling.
  • Optimal fitment: Engineered to ensure a perfect fit and seamless installation.
  • Durable construction: Built with high-quality materials to withstand engine temperatures and environmental conditions.
  • Preventative maintenance: Helps avoid overheating and potential engine damage by ensuring a reliable coolant flow.
  • Vehicle compatibility: Specifically designed for BMW M52 and M54 engine models.

Upgrade your BMW’s cooling system with the BMW M52 M54 Water Pipe from Turner Motorsport for enhanced reliability and performance.

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Radiator Fan Clutch
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:373088
Part#: 11527831619
In Stock
$ 71.83 USD
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Direct replacement


Rein Radiator Hose - Lower - E46
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:379779
Part#: 11531436408
In Stock
$ 31.99 USD
Free Shipping on orders $49 and up
A common source of cooling system failure
Bav Auto Expansion Tank Mounting Plate - E46 Non-M w/ Auto Trans ...
For vehicles with an automatic transmission only
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:638089
Part#: 17111436251
In Stock
Sale - Save 20% $ 45.99

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

$ 36.79 USD
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Sale - Save 20%
$ 45.99

This product was last offered at the strikethrough price on
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$ 36.79 USD
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This Bav Auto part is the mounting bracket from the radiator to the expansion tank on E46 3 series and E85/E86 Z4 with an Automatic Transmission. 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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Thermostat With Housing
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:26494584
Part#: 11537509227
In Stock
Sale - Save 16% $ 60.99

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

$ 50.99 USD
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Sale - Save 16%
$ 60.99

This product was last offered at the strikethrough price on
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$ 50.99 USD
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Bav Auto Radiator Hose - Lower - E46 M52 M54
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
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
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$ 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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Mahle-Behr - Corporate Logo
T#:1735
Part#: 17117573781
In Stock at Vendor
$ 100.99

This product was last offered at the strikethrough price on
04-01-2026

$ 87.99 USD
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$ 87.99 USD
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This coolant reservoir is for the non-M E46 3-series models from 1999-2006 (M3 takes a different expansion tank). 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. This is the most recent expansion tank design from Hella-Behr, the OEM supplier to BMW. It replaces the original BMW part number 17137787039.

Other items to consider replacing at the same time are the radiator cap, coolant level sensor, lower radiator hose, coolant temp sensor in the lower hose, and the hose clamps. If your car has an automatic transmission you should also replace the oil cooler thermostat in the radiator frame, which is a common source for leaks.

This coolant expansion tank fits:

1999-2006 E46 3 series - 323i, 323Ci, 325i, 325Ci, 325xi, 328i, 328Ci, 330i, 330Ci & 330xi (**no M)
2004-2008 X3 SAV - X3 2.5, X3 3.0, X3 3.0si
2000-2005 X5 SAV - X5 3.0
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E46 M3 Radiator Hose - Upper And Lower
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:20617632
Part#: 11537830715KT
In Stock
$ 53.98 USD
Free Shipping on orders $49 and up

Both thermostat housing hoses to replace your worn out rubber and brittle plastic connections.

Over the years and with exposure to extremely hot coolant, the coolant hoses in your vehicle can take a beating. Being made of reinforced rubber, these hoses can fail in a number of ways. Splitting at a hose clamp, swelling, cracking, and breaking are just a few of the ways this hose can leave you stranded. Replace it at the first sign of wear to keep your coolant in your engine.

Comes with both upper and lower thermostat hoses: 11537830715 Lower + 11537830716 Upper

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Expansion Tank Hose
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:27572101
Part#: 64218376153
In Stock
Sale - Save 20% $ 47.99

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

$ 38.34 USD
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Sale - Save 20%
$ 47.99

This product was last offered at the strikethrough price on
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$ 38.34 USD
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OEM Rein Lower Radiator Hose - E46 M3
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:2674
Part#: 11537830715
In Stock
$ 23.99 USD
Free Shipping on orders $49 and up

Replace your cracked or leaking radiator hose to prevent further leaks and potentially catastrophic failure. This hose replaces the lower radiator hose that connects the radiator to the thermostat housing.

This Lower Radiator Hose fits the following BMWs:
2001-2006 E46 3 Series M3, M3 Convertible

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OEM Rein Expansion Tank Hose - E46 3-Series
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:363453
Part#: 64218376153
In Stock
$ 82.99

This product was last offered at the strikethrough price on
05-06-2026

$ 34.99 USD
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$ 34.99 USD
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Expansion tank to heater core

Radiator Hose - Lower
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:38655188
Part#: 11537830715
In Stock
Sale - Save 17% $ 26.99

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

$ 22.53 USD
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Sale - Save 17%
$ 26.99

This product was last offered at the strikethrough price on
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$ 22.53 USD
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Radiator Hose - Upper
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:38621426
Part#: 11537830716
In Stock
Sale - Save 22% $ 25.99

This product was last offered at the strikethrough price on
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$ 20.39 USD
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Sale - Save 22%
$ 25.99

This product was last offered at the strikethrough price on
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BMW Water Pump - Remanufactured - 11517527799
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:372932
Part#: 11517527799
In Stock
$ 42.99 USD
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Features a metal impeller for reliability


Meyle Coolant Expansion Tank - E53 X5, E46 M52/54, E83 X3
5X Entries Into Our F80 M3 Sweepstakes
We Price Match - Give Us A Call or Chat!
Meyle - Corporate Logo
T#:369184
Part#: 17117573781
In Stock
$ 66.99 USD
Free Shipping on orders $49 and up

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.

Other items to consider replacing at the same time are the radiator cap, coolant level sensor, lower radiator hose, coolant temp sensor, and the hose clamps. If your car has an automatic transmission you should also replace the oil cooler thermostat in the radiator frame, which is a common source for leaks.

As a leading source of high-performance BMW parts and accessories since 1993, we at Turner Motorsport are honored to be the go-to supplier for tens of thousands of enthusiasts the world over. With over two decades of parts, service, and racing experience under our belt, we provide only quality performance and replacement parts. All of our performance parts are those we would (and do!) install and run on our own cars, as well as replacement parts that are Genuine BMW or from OEM manufacturers. We only offer parts we know you can trust to perform!

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URO Coolant Expansion Tank - BMW E46 M3
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:48608189
Part#: 17112283344
Ships in 1 Business Day
$ 155.99 USD
Free Shipping on orders $49 and up
​This radiator coolant reservoir/expansion tank for E46 M3 is a common failure item as the plastic weakens and cracks, causing coolant leaks. If your E46 M3 has over 80k miles and still has the original expansion tank, we highly recommend replacing it during your next major service.
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E46 Upper Radiator Hose - 11531436406
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:36981064
Part#: 11531436406
In Stock
$ 31.99

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

$ 24.99 USD
Limited Qty Sale
Free Shipping on orders $49 and up
$ 31.99

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

$ 24.99 USD
Limited Qty Sale
Free Shipping on orders $49 and up

Over time, prolonged exposure to high-temperature coolant can take a toll on your vehicle's hoses. Made from reinforced rubber, these hoses are prone to wear and failure in various ways, including splitting at hose clamps, swelling, cracking, or breaking. Any of these issues can lead to coolant loss and potentially leave you stranded. Replacing your hoses at the first sign of wear is essential to maintaining a properly functioning cooling system.

This replacement hose is designed with the correct diameter, bends, and length for a precise fit, making it an ideal solution for swelled or damaged hoses. With straightforward installation, this hose provides peace of mind, whether you're embarking on a long road trip or simply commuting to work.

When replacing your radiator hose, some coolant loss is unavoidable. Browse our website to find the exact replacement coolant and other parts for your vehicle, delivered straight to your door. Don’t forget to order a new thermostat housing as well—factory plastic units often crack or warp during removal, and replacing them ensures a complete and reliable repair.

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Coolant Expansion Tank - E53 E46 E83 M52 M54
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:373103
Part#: 17137787039
Ships in 1 Business Day
$ 45.99 USD
Free Shipping on orders $49 and up
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.
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URO - Heater Inlet Pipe - E46, Z3, E39
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:34080697
Part#: 11531705210
Ships in 1 Business Day
$ 34.49 USD
Free Shipping on orders $49 and up
This runs from the front left side of the cylinder head under the intake manifold toward the firewall.
BMW Radiator Hose - 11531436408
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:46719183
Part#: CHK0002
In Stock
$ 46.99 USD
Free Shipping on orders $49 and up
Keep your cooling system leak-free and ready for anything with this Rein radiator hose. Over time, heat cycles, pressure, and age take their toll on rubber, leading to soft spots, cracks, or swelling that can quickly turn into a coolant geyser. Rein hoses are built to meet or exceed OEM specs, using premium materials designed to handle extreme temps and high system pressure without breaking a sweat. Each hose features factory-correct fittings, bends, and diameters for a perfect fit—no trimming, stretching, or wrestling required. Whether you’re refreshing your cooling system during a maintenance overhaul or stopping a slow coolant leak before it becomes a major headache, this Rein radiator hose is what you need to get the job done right.
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URO - Corporate Logo
T#:43750239
Part#: 64218376153
In Stock
$ 29.99 USD
Free Shipping on orders $49 and up
Over the years and with exposure to extremely hot coolant, the coolant hoses in your vehicle can take a beating. Being made of reinforced rubber, these hoses can fail in a number of ways. Splitting at a hose clamp, swelling, cracking, and breaking are just a few of the ways this hose can leave you stranded. Replace it at the first sign of wear to keep your coolant in your engine. With the proper diameter, bends, and lengths, this is the perfect replacement for any swelled or damaged hose. An easy installation, it's piece of mind the next time you are on a long trip or your morning commute.
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Water Pipe
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:594365
Part#: 11537502000
In Stock
$ 39.99 USD
Free Shipping on orders $49 and up
Water pipes are essential for proper cooling. If they are cracked, they are going to need to be replaced as soon as possible to avoid overheating your engine. This water pipe runs from the back of the water pump housing to the expansion tank hose. Includes all required seals, needed for the install.
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Expansion Tank Retaining Plate
For vehicles with automatic transmission only
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:362912
Part#: 17111436251
Ships in 1 Business Day
$ 53.99 USD
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$ 53.99 USD
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Mounts to the side of the radiator for retaining the expansion tank

Automatic Transmission Thermostat
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:13661147
Part#: 17111437362
In Stock
$ 43.99

This product was last offered at the strikethrough price on
07-14-2026

$ 34.99 USD
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$ 34.99 USD
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This unit controls the temperature of your automatic transmission fluid
Automatic Transmission Thermostat
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:15511829
Part#: 17 111437362
Ships on Sep 23, 2026
Sale - Save 3% $ 37.99

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

$ 36.85 USD
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Sale - Save 3%
$ 37.99

This product was last offered at the strikethrough price on
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$ 36.85 USD
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Heat exchanger for your automatic transmission, usually changed when you replace your expansion tank.
Water Pump and Seal - with upgraded metal impeller - MEYLE
5X Entries Into Our F80 M3 Sweepstakes
We Price Match - Give Us A Call or Chat!
Meyle - Corporate Logo
T#:579324
Part#: 11517509985
Ships on Sep 16, 2026
$ 52.99 USD
Free Shipping on orders $49 and up

Ensure the optimal performance of your BMW by addressing the crucial component of the water pump. Turner Motorsport provides high-quality water pumps designed to keep coolant flowing smoothly. If left unchecked, a failing water pump can lead to overheating issues, potentially causing damage to engine internals. Common among German vehicles, water pump failure may result in unnecessary visits to the repair shop. Preventive maintenance, especially during timing belt replacements, is essential to avoid rapid coolant temperature rise and potential engine damage.

  • Prevents overheating issues
  • Guards against engine damage
  • Common replacement during timing belt maintenance
  • Ensures smooth coolant flow for optimal engine performance
  • Options for thermostats available on Turner Motorsport's website
  • Convenient coolant replacement options
  • Recommended replacement around 60,000 miles
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Bremmen Parts Water Pump - E46 M3 S54
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:36981065
Part#: 11517838159
Ships on Dec 2, 2026
Sale - Save 20% $ 138.99

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

$ 110.97 USD
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Sale - Save 20%
$ 138.99

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

$ 110.97 USD
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A failing water pump is a recipe for engine overheating and costly internal damage. Keep your coolant flowing and your engine protected by replacing your aging pump with this high-quality OE unit from Bremmen Parts.

Water pump replacement is suggested at 60,000 - 80,000 miles.

This pump includes the alignment dowel, sealing gasket, and thermostat sealing o-ring. We recommend picking up a water pipe sealing o-ring (11537830712) and thermostat (11531318274) for a comprehensive service.

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Expansion Tank Mounting Plate
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:584756
Part#: 17111436250
Ships in 1 Business Day
$ 49.99 USD
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Replace your broken mounting plate to keep your expansion tank secure and prevent leaks.
URO Water Distribution Pipe - E46
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:578992
Part#: 17111707817U
In Stock
$ 27.99

This product was last offered at the strikethrough price on
04-15-2026

$ 22.99 USD
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$ 22.99 USD
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Plastic 3-way flange that brings together lower radiator hose-expansion hose-bypass hose.

Bremmen Parts - Corporate Logo
T#:640140
Part#: 17111712788
Ships on Sep 16, 2026
$ 3.99 USD
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Plastic bleeder screw for cooling system is used to bleed air that would otherwise create an air pocket and lead to overheating. Includes o-ring seal.

Radiator Drain Plug
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:380524
Part#: 17111437361
In Stock
$ 3.99 USD
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Usually stripped out after being removed
Mahle-Behr - Corporate Logo
T#:2766
Part#: 17111742231
Ships in 3 Business Days
$ 20.99

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

$ 19.99 USD
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$ 19.99 USD
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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.

Hailing from Stuttgart, Mahle-Behr specializes in automotive cooling systems. From air conditioning to engine cooling M-B has you covered with OE-quality replacement parts.

This item fits the following BMWs:
1990-1991 E30 BMW 318i 318is 318ic
1992-1998 E36 BMW 318i 318is 318ic 323is 323ic 325i 325is 325ic 328i 328is M3
1999-2005 E46 BMW 323i 323ci 325i 325ci 325xi 328i 328ci 330i 330ci 330xi M3
1989-1995 E34 BMW 530i 535i 540i M5
1991-1995 E34 BMW 525i
1997-2003 E39 BMW 525i 528i 530i 540i M5
1989-1994 E32 BMW 735i 735il 740i 740il 750il
1995-2001 E38 BMW 740i 740il 750il
2002-2008 E65 BMW 745i 745li 750i 750li 760i 760li
1990-1998 E31 BMW 840i 840ci 850i 850ci 850csi
2004-2011 E83 BMW X3 2.5i X3 3.0i X3 3.0si
2000-2006 E53 BMW X5 30.0i X5 4.4i X5 4.6is X5 4.8is
1996-2002 Z3 BMW Z3 1.9 Z3 2.3 Z3 2.5i Z3 2.8 Z3 3.0i M Coupe M Roadster
2003-2008 E85 BMW Z4 2.5i Z4 3.0i Z4 3.0si M Roadster M Coupe
2000-2003 E52 BMW Z8 Z8 Alpina
2007+ E90 BMW 335i & 335xi
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Heater Hose
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:38621424
Part#: 64218363198
Ships in 6 Business Days
Sale - Save 21% $ 10.99

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

$ 8.66 USD
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Sale - Save 21%
$ 10.99

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

$ 8.66 USD
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Water Connection Pipe
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:15511839
Part#: 17111707817
In Stock
Sale - Save 20% $ 18.99

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

$ 15.19 USD
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Sale - Save 20%
$ 18.99

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

$ 15.19 USD
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Connects the radiator to the expansion tank

Rein Heater Hose - E46 BMW
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:362531
Part#: 64218363198
Ships in 3 Business Days
$ 9.58 USD
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Over time, coolant hoses begin to get brittle and are susceptible to cracking and splitting. Replace your cracked or leaking coolant hose to prevent further leaks and potentially catastrophic failure.
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URO Parts Thermostat Assembly - 11537509227
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:29466801
Part#: 11537509227
In Stock
$ 41.99 USD
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$ 41.99 USD
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The thermostat cover in your BMW, made from plastic, is notorious for failing. After years of exposure to hot coolant, the plastic can crack, leading to significant coolant leaks and potential engine overheating.

URO Parts offers a superior solution with their high-quality thermostat cover, designed to surpass the durability of the original factory part. This replacement thermostat comes complete with a gasket for an effortless service.

Features:

Perfect Fit: Guaranteed fitment ensures a seamless replacement process. Optimal Cooling: High-flow OE-style design ensures efficient engine cooling performance. Easy Installation: Manufactured to factory housing dimensions for straightforward bolt-on installation and secure hose connections. Comprehensive Design: Includes ports for temperature sensors where applicable. Superior Materials: Constructed from high-quality alloy or composite materials that resist temperature-induced warping or cracking, preventing coolant leaks. URO Parts, with over 8,000 premium spare parts, specializes in manufacturing precise, durable replacements for factory BMW components. Committed to the highest standards of precision, materials, and workmanship, each part is rigorously tested to deliver the best combination of durability, functionality, and affordability. For reliable replacement parts that offer great value, choose URO Parts.

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Water Pipe - M54 E46 E58 E83
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:36981061
Part#: 11537502000
In Stock
Sale - Save 49% $ 35.99

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

$ 18.50 USD
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Sale - Save 49%
$ 35.99

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

$ 18.50 USD
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Water pipes play a crucial role in maintaining proper engine cooling. If cracked, they must be replaced immediately to prevent engine overheating. This water pipe runs from the rear of the water pump housing to the expansion tank hose. It comes complete with all necessary seals for a hassle-free installation.
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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
$ 4.99 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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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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Auxiliary Fan Switch O-Ring
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:377077
Part#: 13621433077S
In Stock
$ 0.88 USD
Free Shipping on orders $49 and up
Now you can just replace the o-ring instead of the whole switch