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BMW Coolant Expansion Tanks

On certain models, namely E36, E46, and E90, the factory BMW expansion tank is prone to either breaking at connection points or blowing apart altogether. If you're starting to feel like your expansion tank is on borrowed time, it's probably time to replace with either a direct OE replacement, or strengthen your cooling setup with an aluminum expansion tank - we offer numerous performance upgrades for your expansion tank. Especially if you're someone who likes to track your BMW, we recommend upgrading your expansion tank to avoid ruining your track day.
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Coolant Expansion Tank - E46 (non-M), X3, X5 3.0
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:338020
Part#: 17117573781
In Stock
Sale - Save 10% $ 137.99

This product was last offered at the strikethrough price on
08-26-2026

Starting at $ 123.98 USD
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Sale - Save 10%
$ 137.99

This product was last offered at the strikethrough price on
08-26-2026

Starting at $ 123.98 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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OEM Coolant Expansion Tanks Kit - F22/23 F3X B48 B58
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:27605427
Part#: 17138677649TKT
Ships in 1 Business Day
Sale - Save 3% $ 208.99

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

$ 202.62 USD
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Sale - Save 3%
$ 208.99

This product was last offered at the strikethrough price on
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$ 202.62 USD
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Genuine BMW expansion tanks have a bad habit of failing after a few years. This has primarily been caused by the plastic construction of the expansion tanks. After enough heat cycles, the plastic becomes brittle and can crack, causing coolant to leak out and air to enter the coolant system. If a failing expansion tank is not addressed soon enough, the coolant loss can lead to an overheating engine. This kit includes two brand new high quality expansion tanks and caps
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Coolant Expansion Tank - E36/E39/Z3 6 cylinder 1992-1998
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:338018
Part#: 17111723520
Ships in 1 Business Day
$ 99.99

This product was last offered at the strikethrough price on
09-15-2026

Starting at $ 63.18 USD
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Starting at $ 63.18 USD
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This high quality BEHR brand expansion tank is used on M50, M52, S50 and S52 engines, and is a common failure item on all E36 3 series with 6 cylinder engines (325/328/323 and M3) 1992-1999, Z3 with 2.8 liter, MZ3 Roadster/Coupe (S52), and E39 528i from 1997-1998. BEHR was the original equipment supplier to BMW, so you know the BEHR made expansion tank will be the highest quality available. Be leary of competitors selling this part for less -- is it a BEHR? Probably not. We only carry the BEHR brand expansion tank as it is the only one we use in our own BMWs.

If you are overhauling your coolant system, now is the time to consider preventative replacing this expansion tank. These are known to go bad, causing a leak which can leave you stranded. 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.

Need a new coolant level sensor too? If your coolant level sender is bad, your on board computer will constantly display a "low coolant" message (unless your coolant is actually low...). If you're replacing your expansion tank, now is a great time to replace this failure prone sensor. If you want a new coolant level sensor, simply choose from the option below. Because there are different sensors for different year/model BMWs, please be as specific as possible when you give us your car info during checkout (model, year, production date). Thanks!


This item fits the following BMWs:
1992-1998 E36 BMW 323ic 325i 325is 325ic 328i 328is 328ic M3
1997-1998 E39 BMW 528i
1997-1998 Z3 BMW Z3 2.8
1998-2000 Z3 BMW M Roadster M Coupe (S52)
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Expansion Tank Replacement Kit
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:15744017
Part#: N524ECSTNKKT-KT
In Stock
Sale - Save 35% $ 154.99

This product was last offered at the strikethrough price on
04-17-2026

$ 100.95 USD
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Sale - Save 35%
$ 154.99

This product was last offered at the strikethrough price on
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$ 100.95 USD
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The coolant expansion tank in your vehicle gives additional fluid a place to go after expansion and contraction from temperature change. Because it is subjected to such drastic changes on a regular basis, it can often crack or break. You want to keep all the coolant in your vehicle in the cooling system. If your tank has experienced damage such as cracking, nipples breaking off, or mounting point damage, you will need to replace it. The kit includes: Expansion tank with level sensor URO expansion tank cap Genuine BMW expansion tank grommet Genuine BMW mounting bolts
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ECS Cooling System Refresh Kit - Level 1
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:15677493
Part#: 11517527910-KT
In Stock
Sale - Save 1% $ 336.99

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

$ 334.37 USD
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Sale - Save 1%
$ 336.99

This product was last offered at the strikethrough price on
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$ 334.37 USD
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Stop the problems before they arise. If you vehicle has 80,000 miles or more, replace all of these components to ensure that your vehicle stays healthy. To keep everything in top order, continue to replace these components at 80,000 mile intervals. Water pump failure, cracked plastic housings, and expansion tank leaks will not be a concern once all these problem parts are replaced. This kit was put together by Turner including the basic parts that need replaced. Water pump with metal impeller Fan switch Thermostat and thermostat housing Sealing gaskets Expansion tank with level sensor, clamp and cap 1 Gallon Coolant Upper & lower radiator hoses
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Expansion Tank Replacement Kit - E60 M5,E63 M6
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:584232
Part#: 17112283345KT
In Stock
$ 250.99 USD
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$ 250.99 USD
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The expansion tank in your BMW is a vital component of the cooling system, and because of the constant abuse from heat and temperature changes, it often fails. This kit contains all of the basic items needed for a tank replacement.
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ECS Cooling System Refresh Kit - Level 2
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:15677514
Part#: 11281706545-KT
In Stock
Sale - Save 1% $ 474.99

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

$ 470.18 USD
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Sale - Save 1%
$ 474.99

This product was last offered at the strikethrough price on
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$ 470.18 USD
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Stop the problems before they arise. If your BMW has 80,000 miles or more, replace all of these components to ensure that your vehicle stays healthy. Avoid water pump failure, cracked thermostat housings, and expansion tank leaks, which all lead to overheating and subsequent damage. This kit was put together by Turner for a complete cooling system service. GEBA water pump with metal impeller ECS aluminum water pump pulley Fan switch Thermostat and thermostat housing Sealing gaskets Expansion tank with level sensor, clamp and cap 1 Gallon Coolant Upper & lower radiator hoses Accessory drive belts Radiator drain plug
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ECS Cooling System Refresh Kit - Level 2
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:15710821
Part#: 17137607482-KT
In Stock
Sale - Save 19% $ 912.99

This product was last offered at the strikethrough price on
09-14-2026

$ 740.04 USD
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$ 912.99

This product was last offered at the strikethrough price on
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$ 740.04 USD
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As your mileage increases, so does wear and tear on your engine's cooling components. Cooling system components live a rough life, going through extreme temperature changes and being exposed to the elements. A cooling system failure can, and probably will leave you stranded. Included in this kit Water pump with new bolts Thermostat & housing Expansion tank with level sensor Expansion tank cap 1 Gallon of OEM Coolant Waterpump & thermostat hoses Upper and lower radiator hoses Accessory belt
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Cooling System Refresh Kit - Level 2
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:15744066
Part#: 11287837898-KT
Ships on Dec 18, 2026
Sale - Save 6% $ 808.99

This product was last offered at the strikethrough price on
07-15-2026

$ 756.91 USD
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Sale - Save 6%
$ 808.99

This product was last offered at the strikethrough price on
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$ 756.91 USD
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BMW has been designing notoriously failure-prone cooling systems since the late 1980s. The coolant capacity in most BMW engines is not sufficient to accommodate any driving or overheating near red zone temperatures. After the gauge reaches this critical area, it is common for thousands of dollars in damage to occur. Stop the problems before they arise. If your vehicle has 80,000 miles or more, replace all of these components to ensure that your vehicle stays healthy. To keep everything in top order, continue to replace these components at 80,000 mile intervals. Water pump failure, cracked housings, and expansion tank leaks will not be a concern once all these problem parts are replaced. Saleri water pump with metal impeller ECS aluminum water pump pulley Fan switch Vaico Q+ thermostat - made in Germany! Sealing gaskets Expansion tank with level sensor, clamp and cap 1 Gallon Coolant Upper & lower radiator hoses Accessory drive belts Radiator drain plug
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Cooling System Refresh Kit - Level 2 - E9x, E82, E88, Z4
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:42099868
Part#: 11537558523TKT
Back Ordered
Sale - Save 19% $ 829.99

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

$ 670.68 USD
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Keep your BMW running at the proper temperature and avoid costly engine repairs with the Cooling System Refresh Kit, the complete maintenance solution trusted by enthusiasts and professionals alike.
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Cooling System Refresh Kit - Level 2
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:15677500
Part#: 82141467704-KT
Back Ordered
Sale - Save 19% $ 832.99

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

$ 672.46 USD
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Sale - Save 19%
$ 832.99

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As your mileage increases, so does wear and tear on your engine's cooling components. Cooling system components live a rough life, going through extreme temperature changes and being exposed to the elements. A cooling system failure can, and probably will leave you stranded. For automatic transmission (or DCT) vehicles only This kit includes: Thermostat with mounting hardware 1 gallon of BMW coolant Water pump with mounting hardware Primary cooling system hoses and radiator hose gasket, and bleeder screw Expansion tank with cap Accessory belt
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Automatic Transmission Thermostat Kit
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:57122955
Part#: 17111438819KT2
Back Ordered
New Item
$ 93.66 USD
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Keeping your E53 X5 automatic transmission cool is essential for longevity and peak performance. The factory transmission thermostat circuit relies on plastic housings and o-ring seals that deteriorate over time. When the transmission thermostat fails or it's mounting assembly cracks, coolant loss follows putting your transmission at risk of overheating under load.
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Bavarian Autosport - Corporate Logo
T#:638094
Part#: 17111723520
In Stock
Sale - Save 20% $ 39.99

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

$ 31.99 USD
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Sale - Save 20%
$ 39.99

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

$ 31.99 USD
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Replace your old expansion tank to prevent potential failure or leaks. Includes a brand new coolant level sensor. 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 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
05-03-2026

$ 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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Precision Raceworks - Corporate Logo
T#:38229115
Part#: 622-0079
In Stock
$ 69.99 USD
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The E9X / E8X Coolant Tank & Power Steering Bracket w/ Harness is all of the hardware necessary to relocate your power steering pump and install a factory coolant tank on the driver's side of your vehicle. These are the same high-quality components that are included with our E9X/ E8X relocated inlet kits.
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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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$ 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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BMW N47 N55 Expansion Tank
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:17704781
Part#: 17137642160
In Stock
Sale - Save 20% $ 98.99

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

$ 79.19 USD
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Sale - Save 20%
$ 98.99

This product was last offered at the strikethrough price on
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$ 79.19 USD
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BMW N47 N55 Expansion Tank from Turner Motorsport is a high-quality replacement designed to address issues with cracked or damaged coolant expansion tanks. Engineered for durability and performance, this expansion tank ensures reliable cooling system function.

  • Durable Construction: Built to withstand high temperatures and pressure, ensuring long-term reliability.
  • Direct Replacement: Engineered as a precise fit for BMW N47 and N55 engines, making installation straightforward and hassle-free.
  • Enhanced Cooling Efficiency: Maintains optimal coolant levels and pressure for effective engine cooling.
  • High-Quality Materials: Manufactured from premium materials to resist cracking and leaks.
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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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Bav Auto Coolant Expansion Tank - BMW E90 335d M57 3.0L
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:640493
Part#: 17138570079
In Stock
Sale - Save 20% $ 78.99

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

$ 63.19 USD
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Sale - Save 20%
$ 78.99

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

$ 63.19 USD
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Replace your damaged expansion tank to prevent coolant loss or potential overheating issues. 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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Bavarian Autosport - Corporate Logo
T#:638093
Part#: 17138621092
In Stock
Sale - Save 20% $ 60.99

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

$ 48.79 USD
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Sale - Save 20%
$ 60.99

This product was last offered at the strikethrough price on
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$ 48.79 USD
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Replace your old expansion tank to prevent potential failure or leaks. Includes a brand new coolant level sensor.

Precision Raceworks - Corporate Logo
T#:38161689
Part#: 201-0393-BLU
In Stock
$ 109.99 USD
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BMW Blue Engine Coolant Reservoir Cap is the perfect upgrade for BMW owners looking to enhance both the performance and appearance of their engine bay. Constructed from high-quality billet aluminum, this cap replaces the flimsy plastic factory cap, offering improved durability and a sleek, high-performance aesthetic.

Designed with precision, this coolant reservoir cap incorporates the OEM pressure relief function to maintain proper cooling system operation. Unlike inferior stick-on covers that may loosen over time, this cap is a complete replacement, ensuring a secure, leak-free fit. The blue anodized finish provides superior corrosion resistance, making it a reliable upgrade for daily drivers and track enthusiasts alike.

  • OEM pressure relief function – Ensures proper cooling system performance and safety
  • Billet aluminum construction – Provides enhanced durability and strength over factory plastic caps
  • Direct-fit replacement – Fully replaces the stock cap for a precise, secure fit
  • Blue anodized finish – Resists corrosion, heat, and wear for long-lasting performance
  • Motorsport-inspired design – Adds a sleek, professional look to the engine bay
  • Built for longevity – Engineered to withstand extreme temperatures and coolant exposure

Upgrade your BMW’s cooling system with the BMW Blue Engine Coolant Reservoir Cap, designed for superior reliability and style.

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Precision Raceworks - Corporate Logo
T#:38128032
Part#: 201-0394-SIL
Ships in 7 Business Days
$ 94.99 USD
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BMW Silver Auxiliary Coolant Reservoir Cap is the perfect upgrade for BMW owners looking to enhance both the aesthetics and functionality of their engine bay. Unlike generic aftermarket caps that overlook critical pressure regulation, this precision-engineered cap retains the OEM pressure release functionality, ensuring safe and reliable coolant system performance.

Crafted from high-quality billet aluminum, this reservoir cap offers superior durability and resistance to heat and fluids, preventing warping or degradation over time. Unlike adhesive-based cap covers that can loosen or fall off, this cap is a direct replacement for the factory component, providing a secure, high-performance solution.

  • OEM pressure release functionality – Maintains proper system regulation for optimal coolant performance
  • Premium billet aluminum construction – Offers enhanced durability and longevity
  • Direct replacement design – Secure fit without adhesives or modifications
  • Resistant to heat and fluids – Ensures long-lasting reliability in extreme conditions
  • Performance-inspired look – Adds a sleek, high-end appearance to your engine bay
  • Upgraded durability – Prevents cracking, leaks, and premature wear

Upgrade your BMW’s cooling system with the BMW Silver Auxiliary Coolant Reservoir Cap, blending performance, reliability, and premium styling.

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Precision Raceworks - Corporate Logo
T#:38161688
Part#: 201-0393-BLK
Ships in 9 Business Days
$ 109.99 USD
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BMW Black Engine Coolant Reservoir Cap is a premium upgrade designed to enhance both the functionality and aesthetics of your BMW’s engine bay. Unlike flimsy plastic OEM caps, this high-performance cap is CNC-machined from durable billet aluminum, providing long-lasting strength and a sleek, motorsport-inspired look.

Built with precision, this cap retains the essential OEM pressure release function, ensuring proper cooling system operation without compromise. Unlike inferior adhesive covers that may detach over time, this cap fully replaces the factory component, delivering a secure and reliable fit. With a corrosion-resistant black anodized finish, it withstands extreme temperatures and harsh conditions while elevating your BMW’s under-hood appearance.

  • OEM pressure regulation – Maintains factory-designed pressure release for optimal cooling performance
  • CNC-machined billet aluminum – Provides exceptional durability and long-term reliability
  • Direct replacement – Fully replaces the stock cap, ensuring a perfect fit without modifications
  • Corrosion-resistant anodized finish – Prevents wear and adds a stealthy, high-performance look
  • Heat and fluid-resistant design – Built to withstand extreme temperatures and coolant exposure
  • Enhanced engine bay styling – Offers a sleek, motorsport-inspired upgrade

Upgrade your BMW’s cooling system with the BMW Black Engine Coolant Reservoir Cap, designed for superior performance and long-lasting durability.

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Precision Raceworks - Corporate Logo
T#:47679259
Part#: 622-0291-SIL
In Stock
$ 184.99 USD
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$ 184.99 USD
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The Precision Raceworks Billet Coolant Cap Set is a functional and stunningly stylish way to add a nice touch to any engine bay! These caps come in three color options, so there is always a color that will work for you! Black with Billet Silver, Black with Blue, and the Stealth series (all black). Many people don't realize it, but the OEM caps have a pressure release valve built into them. Oftentimes, aftermarket companies don't know this either or just don't care. But our team cares about proper function just as much as we care about the appearance of every product we design. For pressure relief, our caps incorporate the OEM internals, so you get all the functionality of the original caps, ensuring a safe and reliable system in place. These caps offer superior style and performance-grade components that guarantee a reliable fit every time. Durable billet aluminum construction provides long-lasting protection and dependability that will upgrade your engine bay for years to come. PLEASE NOTE: These do require assembly and swapping the pressure relief valves from your old caps to your new billet caps.
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Precision Raceworks - Corporate Logo
T#:38094357
Part#: 601-0055
Ships in 5 Business Days
$ 39.99 USD
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This driver-side coolant tank mounting bracket set is ideal for those with relocated inlets or single turbo kits. It enables you to reposition your factory coolant tank to the driver's side of the engine bay. Best of all, it’s fully compatible with all known charge pipes.
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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
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$ 13.99

This product was last offered at the strikethrough price on
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$ 11.89 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. 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 Coolant Level Sensor - BMW E36 E39 M50/52 S50/52
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:639793
Part#: 61318360855
In Stock
Sale - Save 19% $ 20.99

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

$ 16.99 USD
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$ 20.99

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$ 16.99 USD
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This is the sensor / sending unit that notifies the computer if your coolant level is low. When this fails, it can give a false indication of low coolant -- or worse, not inform you of a low coolant situation that could potentially cause overheating. 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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Precision Raceworks - Corporate Logo
T#:1332002
Part#: 201-0050
In Stock
$ 19.99 USD
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The E9X/ E8X coolant tank level sensor extension harness is the same great product that comes standard with Precision Raceworks' E9X/ E8X relocated inlet kits. The coolant tank level sensor extension harness is perfect for those running a relocated coolant reservoir tank or 335D coolant reservoir. This harness plugs right into the factory connector allowing you to extend the position of the sensor without the need to splice any wires.
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Precision Raceworks - Corporate Logo
T#:38161691
Part#: 201-0393-SIL
Ships in 8 Business Days
$ 109.99 USD
Free Shipping on orders $49 and up

BMW Silver Engine Coolant Reservoir Cap is a premium upgrade for BMW owners looking to enhance both the performance and appearance of their engine bay. Crafted from high-strength billet aluminum, this cap replaces the factory plastic version, offering superior durability and a refined, professional look.

Designed with functionality in mind, it integrates the OEM pressure relief system to ensure your engine's cooling system remains safe and efficient. Unlike adhesive covers, which can peel or wear over time, this cap is a direct-fit replacement, providing a secure and leak-proof seal. The silver anodized finish not only enhances the visual appeal but also ensures resistance to corrosion, high temperatures, and wear, making it perfect for daily driving and track use.

  • OEM pressure relief integration – Maintains proper cooling system performance and reliability
  • Durable billet aluminum – Outperforms factory plastic caps in longevity and strength
  • Precision-machined for perfect fitment – Replaces the stock cap securely, not just a cover
  • Anodized silver finish – Offers corrosion, heat, and wear resistance
  • Elevates engine bay aesthetics – Adds a clean, professional appearance
  • Built for both street and track use – Designed to withstand extreme conditions

Enhance your BMW’s cooling system with the BMW Silver Engine Coolant Reservoir Cap, providing both style and functionality for years to come.

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Precision Raceworks - Corporate Logo
T#:38128031
Part#: 201-0394-BLK
Ships in 9 Business Days
$ 94.99 USD
Free Shipping on orders $49 and up

BMW Black Auxiliary Coolant Reservoir Cap is the perfect upgrade for BMW owners looking to enhance both the aesthetics and functionality of their engine bay. Unlike generic aftermarket caps that overlook critical pressure regulation, this precision-engineered cap retains the OEM pressure release functionality, ensuring safe and reliable coolant system performance.

Crafted from high-quality billet aluminum, this reservoir cap offers superior durability and resistance to heat and fluids, preventing warping or degradation over time. Unlike adhesive-based cap covers that can loosen or fall off, this cap is a direct replacement for the factory component, providing a secure, high-performance solution.

  • OEM pressure release functionality – Maintains proper system regulation for optimal coolant performance
  • Premium billet aluminum construction – Offers enhanced durability and longevity
  • Direct replacement design – Secure fit without adhesives or modifications
  • Resistant to heat and fluids – Ensures long-lasting reliability in extreme conditions
  • Performance-inspired look – Adds a sleek, high-end appearance to your engine bay
  • Upgraded durability – Prevents cracking, leaks, and premature wear

Upgrade your BMW’s cooling system with the BMW Black Auxiliary Coolant Reservoir Cap, blending performance, reliability, and premium styling.

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Precision Raceworks - Corporate Logo
T#:38128029
Part#: 201-0394-BLU
Ships in 9 Business Days
$ 94.99 USD
Free Shipping on orders $49 and up

BMW Blue Auxiliary Coolant Reservoir Cap is the perfect upgrade for BMW owners looking to enhance both the aesthetics and functionality of their engine bay. Unlike generic aftermarket caps that overlook critical pressure regulation, this precision-engineered cap retains the OEM pressure release functionality, ensuring safe and reliable coolant system performance.

Crafted from high-quality billet aluminum, this reservoir cap offers superior durability and resistance to heat and fluids, preventing warping or degradation over time. Unlike adhesive-based cap covers that can loosen or fall off, this cap is a direct replacement for the factory component, providing a secure, high-performance solution.

  • OEM pressure release functionality – Maintains proper system regulation for optimal coolant performance
  • Premium billet aluminum construction – Offers enhanced durability and longevity
  • Direct replacement design – Secure fit without adhesives or modifications
  • Resistant to heat and fluids – Ensures long-lasting reliability in extreme conditions
  • Performance-inspired look – Adds a sleek, high-end appearance to your engine bay
  • Upgraded durability – Prevents cracking, leaks, and premature wear

Upgrade your BMW’s cooling system with the BMW Blue Auxiliary Coolant Reservoir Cap, blending performance, reliability, and premium styling.

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Precision Raceworks - Corporate Logo
T#:47679257
Part#: 622-0291-BLAK
Ships in 9 Business Days
$ 184.99 USD
Free Shipping on orders $49 and up
$ 184.99 USD
Free Shipping on orders $49 and up
The Precision Raceworks Billet Coolant Cap Set is a functional and stunningly stylish way to add a nice touch to any engine bay! These caps come in three color options, so there is always a color that will work for you! Black with Billet Silver, Black with Blue, and the Stealth series (all black). Many people don't realize it, but the OEM caps have a pressure release valve built into them. Oftentimes, aftermarket companies don't know this either or just don't care. But our team cares about proper function just as much as we care about the appearance of every product we design. For pressure relief, our caps incorporate the OEM internals, so you get all the functionality of the original caps, ensuring a safe and reliable system in place. These caps offer superior style and performance-grade components that guarantee a reliable fit every time. Durable billet aluminum construction provides long-lasting protection and dependability that will upgrade your engine bay for years to come. PLEASE NOTE: These do require assembly and swapping the pressure relief valves from your old caps to your new billet caps.
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Bavarian Autosport - Corporate Logo
T#:640491
Part#: 17137542986
Special Order: No Guaranteed ETA
Sale - Save 10% $ 54.99

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

$ 49.49 USD
Free Shipping on orders $49 and up
Sale - Save 10%
$ 54.99

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

$ 49.49 USD
Free Shipping on orders $49 and up
This Bav Auto cooling system expansion tank/coolant reservoir is a direct replacement for the factory unit. Replace your cracked or leaking radiator expansion tank today. 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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