BMW Coolant Expansion Tanks for BMW 3 Series E30 (1984-1991)

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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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ECS Tuning Aluminum Coolant Bleeder Screw
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T#:363070
Part#: 003530ECS01A
In Stock
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This product was last offered at the strikethrough price on
06-13-2026

$ 26.99 USD
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$ 35.99

This product was last offered at the strikethrough price on
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$ 26.99 USD
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Replace the flimsy plastic bleeder screw used in the coolant expansion tank or in one of the cooling system hoses with this high quality, durable, aluminum bleeder screw. The stock plastic screw can deform over time due to heat or even regular use. We have even seen the head of the screw snap off, leaving the threaded body stuck in the expansion tank. This aluminum screw will help to prevent sudden failure of the bleeder screw, which can result in immediate overheating of the car.

ECS Tuning's Aluminum Coolant Bleeder Screw replaces Genuine BMW Part Number 17111712788

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Genuine BMW Expansion Tank Cap - E3X / E53 / Z4
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Genuine BMW - Corporate Logo
T#:207187
Part#: 17117639022
In Stock
21% off MSRP $ 34.96

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$ 27.67 USD
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21% off MSRP
$ 34.96

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 27.67 USD
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Genuine BMW Radiator Cap - 2,0Bar
This item fits the following BMW Chassis:
E36 M3,E39 M5,E46 M3,E85 Z4M,E53 48IS,E36,E38,E39,E46,E53 X5,E65,E83 X3,E85 Z4,E86 Z4,F06,F10,F12,F13

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URO Coolant Expansion Tank - E30 325e 325i 88-91
For vehicles with production date from 09/1987
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T#:2453609
Part#: 17111712641
In Stock
$ 46.99 USD
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$ 46.99 USD
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This coolant reservoir is for the E30 325i 1988-1991. We have found that the expansion tanks should be replaced based on age as well as condition. This item fits the following BMWs: 1988-1991 E30 BMW 325e 325es 325i 325ic 325is 325ix
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Mahle-Behr Coolant Expansion Tank - E30
For vehicles with production date from 09/1987
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Mahle-Behr - Corporate Logo
T#:399336
Part#: 17111712641
In Stock at Vendor
$ 56.99 USD
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$ 56.99 USD
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Replace your cracked or faded expansion tank.

Genuine BMW Radiator Cap 1,4Bar - 17112227683 - E30,E30 M3, E28 M5 ...
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Genuine BMW - Corporate Logo
T#:22513
Part#: 17112227683
In Stock
4% off MSRP $ 27.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 26.99 USD
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4% off MSRP
$ 27.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 26.99 USD
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Genuine BMW Radiator Cap - 1,4Bar
This item fits the following BMW Chassis:
E30 M3,E30

Fits BMW Engines including:
S14,S38

Coolant Level Sensor - E30 87-91, E32 E34
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Febi - Corporate Logo
T#:1728
Part#: 61311378320
Ships in 3 Business Days
$ 23.99

This product was last offered at the strikethrough price on
06-04-2026

$ 23.22 USD
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$ 23.22 USD
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Coolant level sensor for most E30, E32, and E34 cars. Fits E30 M3 and all E30 325's; E32 735, 740, and 750; and E34 530, 535, 540, and M5. 

Since the late 1800’s Febi has been fabricating replacement metal parts. This history is self evident in the quality and vast amount of applications they service. With more than 34,000 repair solutions for cars and commercial vehicles you can be sure Febi has you covered.

This item fits the following BMWs:
1987-1991 E30 BMW 318i 318is 318ic 325e 325es 325i 325is 325ic 325xi M3
1989-1995 E34 BMW 530i 535i 540i M5
1987-1989 E24 BMW 635csi M6
1988-1994 E32 BMW 735i 735il 740i 740il 750il

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Genuine BMW Expansion Tank Cap
For vehicles with production date from 09/1987
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Genuine BMW - Corporate Logo
T#:384985
Part#: 17137639023
In Stock
$ 21.99 USD
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$ 21.99 USD
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Coolant Expansion Tank - E30 325e 325i thru 1987 528e thru 88 ...
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Genuine BMW - Corporate Logo
T#:2061
Part#: 17111707540
In Stock
Sale - Save 8% $ 158.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 146.98 USD
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$ 158.99

This product was last offered at the strikethrough price on
06-15-2026

$ 146.98 USD
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This radiator expansion tank (coolant reservoir) is used on E30 325e 325es 325i 325is 325ic from 1984-1987 and E28 528e 1982-1987.

When doing any sort of repair or maintenance there is no replacement for genuine factory parts. Turner Motorsport carries the Genuine BMW brand with pride and has the parts you need to complete your next project with confidence.​

This item fits the following BMWs:
1984-1987 E30 BMW 325e 325es 325i 325is 325ic 325ix
1982-1988 E28 BMW 528e
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Coolant Expansion Tank - E30 M3 1988-1991
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Genuine BMW - Corporate Logo
T#:12562
Part#: 17112225543
In Stock
5% off MSRP $ 215.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 204.99 USD
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5% off MSRP
$ 215.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 204.99 USD
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This Genuine BMW cooling system expansion tank / coolant reservoir is a direct replacement for the factory unit. Replace your cracked or leaking radiator expansion tank today and save your valuable S14 engine for damage.

When doing any sort of repair or maintenance there is no replacement for genuine factory parts. Turner Motorsport carries the Genuine BMW brand with pride and has the parts you need to complete your next project with confidence.

This item fits the following BMWs:
1988-1991 E30 BMW M3
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Genuine BMW Cap - 17121719356 - E30,E46,E46 M3
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Genuine BMW - Corporate Logo
T#:46115
Part#: 17121719356
Ships in 4 Business Days
3% off MSRP $ 31.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 30.99 USD
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3% off MSRP
$ 31.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 30.99 USD
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Genuine BMW Cap
This item fits the following BMW Chassis:
E46 M3,E30,E46

Fits BMW Engines including:
M20,S54,S62

OEM Mahle-Behr Coolant Expansion Tank - E30 E36 318i/is (M42/M44), E3...
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Mahle-Behr - Corporate Logo
T#:363898
Part#: 17111712835
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$ 20.99 USD
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This high quality Hella/BEHR brand expansion tank is used on M42, M44, M50, M52, engines, and is a common failure item on all E36 3 series with 4 cylinder engines (318i/is/ti/ic) 1990-1999, Z3 with 1.9 liter and E34 525i from 1989-1995. Hella/BEHR was the original equipment supplier to BMW, so you know the Hella/BEHR made expansion tank will be the highest quality available. Be leary of competitors selling this part for less -- is it a Hella/BEHR? Probably not. We only carry the Hella/BEHR brand expansion tank as it is the only one we use in our own BMWs.

Hella is a premium manufacturer that supplies automotive parts to numerous car brands across the world. Everything from electrical to mechanical genuine parts have been made and supplied directly to BMW before the vehicles ever leave the production floor. Their high quality, long lasting parts have made them a trusted brand chosen to help keep your BMW on the road for many years to come.

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!

This item fits the following BMWs:
1990-1991 E30 BMW 318i 318is 318ic
1992-1998 E36 BMW 318i 318is 318ti 318ic
1989-1995 E34 BMW 525i
1996-1998 Z3 BMW Z3 1.9

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Moroso Aluminum Coolant Expansion Tank - E30 M3
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Moroso - Corporate Logo
T#:29666103
Part#: 63799
In Stock at Vendor
$ 459.99 USD
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The coolant expansion tank provides hot coolant with a place to travel, preventing pressure buildup within your cooling system. On many BMWs, this component is constructed from plastic. While cheap to replace and manufacture, a failed cooling tank can cause costly engine damage.

With this issue in mind, Moroso designed a high-quality replacement. Featuring TIG welded, 100% aluminum construction, this tank is sure to outperform it's factory counterpart.

Features:

Bolt-in replacement for stock cracked or discolored tanks Fabricated aluminum Features billet aluminum filler neck and integrated sight glass to monitor coolant level Can be polished, painted, powder coated or left as-is Moroso radiator cap (63320) included

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Genuine BMW Coolant Level Sensor
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Genuine BMW - Corporate Logo
T#:368499
Part#: 61311378320
Ships in 2 Business Days
3% off MSRP $ 92.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 89.99 USD
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3% off MSRP
$ 92.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 89.99 USD
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Genuine BMW Coolant Expansion Tank
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Genuine BMW - Corporate Logo
T#:360743
Part#: 17111712835
Ships in 1-2 days
6% off MSRP $ 141.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 133.99 USD
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6% off MSRP
$ 141.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 133.99 USD
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Genuine BMW Expansion Tank Cap
For vehicles with production date up to 09/1987
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Genuine BMW - Corporate Logo
T#:367910
Part#: 17114379047
Ships in 2 Business Days
4% off MSRP $ 47.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 45.99 USD
Free Shipping on orders $49 and up
4% off MSRP
$ 47.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 45.99 USD
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Coolant Level Sensor - E30 325e,5/84/86, E28, E24, E23
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Genuine BMW - Corporate Logo
T#:10545
Part#: 61311375715
Ships in 1-2 days
3% off MSRP $ 92.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 89.99 USD
Free Shipping
3% off MSRP
$ 92.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 89.99 USD
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Got a low coolant level warning light on the dash? We recommend you check this coolant level sensor as it is often the cause of erroneous warning lights.
This item fits the following BMW's:
5/1984-1986 E30 BMW 325e 325es
5/1984-1988 E28 BMW 524td 528e 533i 535i 535is M5
5/1984-1988 E24 BMW 633csi 635csi
5/1984-1987 E23 BMW 733i 735i
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Expansion Tank - E30
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Genuine BMW - Corporate Logo
T#:45011
Part#: 16131178014
Ships in 7 Business Days
4% off MSRP $ 373.00

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 358.99 USD
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4% off MSRP
$ 373.00

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 358.99 USD
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Genuine BMW Expansion Tank

This item fits the following BMW Chassis:
E30 M3,E30

Fits BMW Engines including:
M10,M20,M42,S14

Coolant Expansion Tank - E30 325e 325i 88-91
For vehicles with production date from 09/1987
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Genuine BMW - Corporate Logo
T#:7428
Part#: 17111712641
Ships in 5 Business Days
4% off MSRP $ 164.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 158.99 USD
Free Shipping
4% off MSRP
$ 164.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 158.99 USD
Free Shipping
This coolant reservoir is for the E30 325i 1988-1991. We have found that the expansion tanks should be replaced based on age as well as condition.

When doing any sort of repair or maintenance there is no replacement for genuine factory parts. Turner Motorsport carries the Genuine BMW brand with pride and has the parts you need to complete your next project with confidence.​

This item fits the following BMWs:
1988-1991 E30 BMW 325e 325es 325i 325ic 325is 325ix
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OEM Behr Coolant Expansion Tank Cap - E36 E46 E34 E39 E32 E38 E65 X3 ...
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Mahle-Behr - Corporate Logo
T#:2766
Part#: 17111742231
In Stock
$ 19.99 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.

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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Expansion Tank Cap - 1.4 Bar - E36 318i 323i 325i 328i M3
For vehicles with production date from 09/1987
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Febi - Corporate Logo
T#:340717
Part#: 17111742232
In Stock at Vendor
$ 24.99

This product was last offered at the strikethrough price on
06-18-2026

$ 9.99 USD
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$ 9.99 USD
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This expansion tank cap, from the E30 325is, is designed to give way at 20 PSI instead of 30 PSI, like the stock cap. In the event the system over-pressurizes, this cap should let go first, potentially saving your radiator, hoses, or other vital cooling system components. While there's no guarantee it will save your radiator, this small part could mean the difference between calling a tow service and making it home, and a little extra insurance never hurt. This cap is a high-quality aftermarket part from an OE supplier.

Fits the Following BMWs:

E36 318i 323i 325i 328i M3

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Bremmen Coolant Bleeder Screw - BMW E30 E36 E38 E39 E46 E83 E90 Z4 ...
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Bremmen Parts - Corporate Logo
T#:640140
Part#: 17111712788
In Stock
Sale - Save 39% $ 3.99

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

$ 2.44 USD
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Sale - Save 39%
$ 3.99

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

$ 2.44 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.

Coolant Level Sensor
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Bremmen Parts - Corporate Logo
T#:30728984
Part#: 61311378320
In Stock
Sale - Save 56% $ 34.99

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

$ 15.29 USD
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Sale - Save 56%
$ 34.99

This product was last offered at the strikethrough price on
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$ 15.29 USD
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Bav Auto Expansion Tank Cap - E36 E46 E34 E39 E32 E38 E65 X3 X5 Z4 ...
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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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Sale - Save 15%
$ 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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Meyle Expansion Tank Cap
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Meyle - Corporate Logo
T#:579357
Part#: 3148009004
In Stock
Sale - Save 40% $ 14.99

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

$ 8.99 USD
Free Shipping on orders $49 and up
Sale - Save 40%
$ 14.99

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

$ 8.99 USD
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Replace worn or missing pieces.


OEM Rein Expansion Tank Cap - BMW E32 E34 E36 E38 E39 E46 & More ...
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Rein - Corporate Logo
T#:340541
Part#: 17111742231
In Stock
Sale - Save 5% $ 17.99

This product was last offered at the strikethrough price on
06-29-2026

$ 17.09 USD
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Sale - Save 5%
$ 17.99

This product was last offered at the strikethrough price on
06-29-2026

$ 17.09 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.
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Rein Expansion Tank Cap - E30, E34
For vehicles with production date from 09/1987
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
2X Entries For Our G87 M2 Sweepstakes! We Price Match - Give Us A Call or Chat!
Rein - Corporate Logo
T#:592018
Part#: 17137639023
Ships in 3 Business Days
Sale - Save 5% $ 14.99

This product was last offered at the strikethrough price on
06-29-2026

$ 14.24 USD
Free Shipping on orders $49 and up
Sale - Save 5%
$ 14.99

This product was last offered at the strikethrough price on
06-29-2026

$ 14.24 USD
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1.4 Bar pressure
OEM Mahle-Behr Coolant Expansion Tank Cap - E30 325e/i 1988-91, E34 5...
For vehicles with production date from 09/1987
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Mahle-Behr - Corporate Logo
T#:369633
Part#: 17111742232
Ships in 1 Business Day
$ 18.99 USD
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$ 18.99 USD
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This radiator expansion tank cap fits E30 325e 325es 325i 325is 325ix 325ic with M20 engine from 1988 . 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.

This item fits the following BMWs:
1988-1991  E30 BMW  325e 325es 325i 325ic 325is 325ix
1989-1990  E34 BMW  525i with M20 engine
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URO Coolant Expansion Tank - BMW E30 E36 Z3 M42 M44, E34 325 ...
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URO - Corporate Logo
T#:362008
Part#: 17111712835
Ships in 1 Business Day
$ 18.99 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
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Expansion Tank Cap
For vehicles with production date from 09/1987
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MTC - Corporate Logo
T#:371228
Part#: 17111742232
Ships in 9 Business Days
$ 6.99 USD
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$ 6.99 USD
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1.4 Bar pressure. Older radiator caps being to lose their ability to hold pressure over time. Resulting in a lower boiling point for the coolant system.
2 Pin Connector
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ECS - Corporate Logo
T#:33412932
Part#: 61132359999
Ships on Jul 28, 2026
Sale - Save 25% $ 10.99

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

$ 8.24 USD
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Sale - Save 25%
$ 10.99

This product was last offered at the strikethrough price on
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$ 8.24 USD
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Includes connector housing with terminals and seals. Commonly used for the coolant level sensor.

ECS Tuning replacement harness connectors include all necessary pins and wire seals for a complete harness repair. Whether you have a broken harness connector or need a complete wiring repair, we have the components you need.

Each connector includes an additional terminal in case one becomes lost or damaged during installation.

*OEM cross reference PN# 61132359999 - Commonly used for the coolant level sensor.

Please reference the original part number from the existing connector to confirm fitment, before ordering.

Suggested tools:

Suggested crimping pliers: T#387193
Wire De-pin tools:
12pc De-Pin Tool Set - T#386379
23pc De-Pin Tool Set - T#641943

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Meyle Expansion Tank Cap
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Meyle - Corporate Logo
T#:5958735
Part#: 17111742232
Special Order: No Guaranteed ETA
$ 10.99 USD
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Wulf Gaertner Autoparts AG manufactures and markets automotive spare parts under its MEYLE brand. Since its foundation in 1958, Wulf Gaertner Autoparts has been an owner-operated, unlisted family business on the aftermarket scene. Since 1995, Wulf Gaertner Autoparts AG has been manufacturing and trading under its MEYLE brand. They pride themselves on top-grade quality-tested spare parts for passenger cars, vans and commercial vehicles. The coolant expansion tank cap keeps necessary pressure on your coolant to increase efficiency. If you have an overheating issue in your vehicle, a simple, quick, and inexpensive part to replace is this cap. Often times, the coolant is not kept under enough pressure to keep it from boiling or expanding too much. This cap keeps all the heat and liquid inside the coolant system for maximum efficiency. Should be replaced each time major coolant system service is performed.
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URO Expansion Tank Cap - BMW E30
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
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URO - Corporate Logo
T#:592118
Part#: 17111468077
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$ 6.99 USD
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URO Expansion Tank Cap - BMW E30

The URO Expansion Tank Cap - BMW E30 is a crucial component for maintaining optimal cooling system performance by ensuring proper pressure regulation. Over time, older radiator caps lose their ability to hold pressure, leading to a lower boiling point and potential overheating issues. This high-quality replacement cap is designed to restore factory pressure levels, preventing coolant loss and maintaining engine efficiency. Crafted from durable materials, it resists wear and temperature fluctuations, ensuring long-lasting reliability.

  • Direct replacement for BMW E30 models
  • Maintains correct cooling system pressure to prevent overheating
  • Helps sustain optimal engine temperature and performance
  • High-quality construction for durability and reliability
  • Prevents coolant evaporation and system inefficiencies
  • Easy installation with OE-style fitment
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Expansion Tank Cap
For vehicles with production date up to 09/1987
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
2X Entries For Our G87 M2 Sweepstakes! We Price Match - Give Us A Call or Chat!
URO - Corporate Logo
T#:362007
Part#: 17114379047
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$ 7.99 USD
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$ 7.99 USD
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1.2 Bar pressure

Coolant Expansion Tank With Cap - 17111712835
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Rein - Corporate Logo
T#:46616014
Part#: EPK0012
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Sale - Save 8% $ 29.99

This product was last offered at the strikethrough price on
06-29-2026

$ 27.65 USD
Free Shipping on orders $49 and up
Sale - Save 8%
$ 29.99

This product was last offered at the strikethrough price on
06-29-2026

$ 27.65 USD
Free Shipping on orders $49 and up
The coolant expansion tank provides a place for excess fluid as coolant expands and contracts with temperature changes. Constant exposure to these extremes can cause the tank to crack, break, or suffer damage to its nipples or mounting points. To keep your cooling system sealed and functioning properly, any damaged tank should be replaced.
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