BMW Coolant Expansion Tanks for BMW E93 M3 S65 4.0L

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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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ECS - Corporate Logo
T#:363070
Part#: 003530ECS01A
In Stock
Sale - Save 25% $ 35.99

This product was last offered at the strikethrough price on
06-13-2026

$ 26.99 USD
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Sale - Save 25%
$ 35.99

This product was last offered at the strikethrough price on
06-13-2026

$ 26.99 USD
Free Shipping on orders $49 and up

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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Coolant Expansion Tank Cap - E9x M3, E60 E63 F01 E70 E71
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Genuine BMW - Corporate Logo
T#:194502
Part#: 17117639021
In Stock
22% 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.

$ 27.29 USD
Free Shipping on orders $49 and up
22% 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.

$ 27.29 USD
Free Shipping on orders $49 and up
This radiator expansion tank cap is used most BMW's from 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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AutoTecknic Dry Carbon Coolant Expansion Tank Cap Cover - Gloss Carbo...
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AUTOTECKNIC - Corporate Logo
T#:39497984
Part#: BM-0803-GC
Ships in 7 Business Days
$ 74.99 USD
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Turner Motorsport offers the AutoTecknic Dry Carbon Coolant Expansion Tank Cap Cover - Gloss Carbon as the perfect addition for BMW owners looking to elevate their engine bay’s appearance with premium materials and precision engineering.
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Meistersatz CAP- EXPANSION TANK
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Meistersatz - Corporate Logo
T#:1195781
Part#: 17117639021
Ships in 3 Business Days
$ 30.99

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

$ 29.99 USD
Free Shipping on orders $49 and up
$ 29.99 USD
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Rein Expansion Tank Cap
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2X Entries For Our G87 M2 Sweepstakes! We Price Match - Give Us A Call or Chat!
Rein - Corporate Logo
T#:384807
Part#: 17117639021
In Stock
$ 16.99 USD
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Cap for plastic expansion tank
Expansion Tank Cap
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2X Entries For Our G87 M2 Sweepstakes! We Price Match - Give Us A Call or Chat!
URO - Corporate Logo
T#:373099
Part#: 17137516004
Ships in 1 Business Day
$ 15.99

This product was last offered at the strikethrough price on
04-10-2026

$ 10.99 USD
Free Shipping on orders $49 and up
$ 10.99 USD
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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.
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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
Free Shipping on orders $49 and up
Sale - Save 25%
$ 10.99

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

$ 8.24 USD
Free Shipping on orders $49 and up

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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Fluid Level Sensor
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Meyle - Corporate Logo
T#:5973204
Part#: 17117546548
Special Order: No Guaranteed ETA
$ 13.99 USD
Free Shipping on orders $49 and up
MEYLE-ORIGINAL: True to OE fluid level sensor. Used in multiple locations. 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. Comparable OE Cross Reference - 17117546548
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Moroso Aluminum Coolant Expansion Tank
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Moroso - Corporate Logo
T#:29666104
Part#: 63850
In Stock at Vendor
$ 586.00 USD
Free Shipping on orders $49 and up

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:

Key Benefits:

Direct bolt-in replacement for stock, 2 piece plastic tank Fabricated Aluminum for strength, factory tanks fail after repeated high heat situations & age Features billet aluminum mounting tab/bleeder assembly for strength and precision No cutting of factory hoses is required and accepts the factory clip-on hose Included is a Moroso (63324) racing radiator cap that operates in the same pressure range as the factory cap Moroso radiator cap mounts to a billet aluminum neck that will not strip out like plastic threaded necks Can be polished, chromed, or powder coated or left as-is

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