Our Turner Motorsport's full aluminum expansion tank was designed and engineered in house to help with the weak point in your N52/N54 cooling system. The coolant expansion tank goes through heat cycles over and over again from regular driving, it is important that your expansion tank is doing its job to retain coolant to keep your engine operating temperatures down and keep your engine bay clean. Not only is this a major upgrade but also a great maintenance item to replace. Our expansion tank was designed to fit the OEM hoses for an easy install and comes with all the upgraded items you will need for a clean install

If your BMW needs a new expansion tank, make sure this is the last expansion tank you ever need to buy. Our coolant expansion tank has a full aluminum construction and wrinkle black powder coat for durability. Expansion tank kit comes with all the accessories you need to replace your expansion tank once, and never have to worry about it again.

Product Features:

Maintains stock coolant capacity and expansion volume
Designed to maintain OE coolant elevation, preventing air pockets
Baffled tank ensures that air pockets cannot be introduced during aggressive driving and provides accurate coolant level reading
Carefully designed bleed passage prevents the introduction of air as the engine cools
Turner engraved internal fill level
TIG welded 5052 aluminum construction
All bungs are machined to fit factory hose ends
Kit contents:

Turner Aluminum Expansion Tank
Coolant level sensor
Expansion tank cap
Heavy duty bleeder screw
Flared coolant pressure release line
Hardware for installation

BMWs are well-known for their problematic cooling systems, which are often a catalyst for irreversible engine damage and a hefty repair bill. The coolant expansion tank—a crucial component responsible for holding hot engine coolant under high pressure—is a common cause of cooling system issues. Unfortunately, BMW chose to manufacture the factory E9X N55 expansion tank out of plastic. After years of exposure to high coolant temperatures, ambient engine bay heat, and chemical-rich antifreeze, the plastic degrades, eventually weakening enough to fail catastrophically.

With this issue in mind, our team of BMW enthusiasts engineered the ultimate cooling system upgrade for E82/88 and E90/92/93 owners: a heavy-duty expansion tank built to last! Crafted from durable 5052 TIG-welded aluminum, this tank resists high temperatures and pressures without degrading over time. Unlike the fragile OEM plastic tank, Turner’s design eliminates the risk of cracking, leaking, or failure. Upgrade to our Heavy Duty Aluminum Expansion Tank Kit and say goodbye to expansion tank issues for good!

To guarantee exact fitment, the upgraded tank was designed using advanced 3D CAD modeling. All bungs, nipples, and fittings are precision-machined to ensure a secure seal with factory hose ends. Unlike other aftermarket options, this tank maintains the factory coolant capacity and includes our laser-cut logo plate at the top, providing an accurate fill level. Internal baffles are incorporated to prevent fluid cavitation, eliminating air pockets in the cooling system and avoiding false coolant level warnings during spirited driving.

Engineered for high-performance builds and daily drivers alike, this expansion tank boasts a premium wrinkle black powder coat finish for a clean "OEM+" aesthetic. This tough coating not only enhances appearance but also protects against corrosion for long-term durability. The kit includes a silicone overflow hose, a high-quality level sensor, and an OE expansion tank cap, offering a complete cooling system upgrade. Avoid the risks of the factory expansion tank—upgrade your N55-equipped BMW today and drive with confidence!

Features & Benefits:

Durable 5052 TIG-Welded Aluminum Construction: Ensures long-term reliability and eliminates expansion tank failure. Premium Wrinkle Black Powder Coat Finish: Offers an "OEM+" appearance while preventing corrosion. Factory Coolant Capacity Retention: Maintains the same coolant level as the original design. Laser-Cut Turner Logo Plate: Provides a clear and accurate fill level indicator. Internal Baffles: Prevent the introduction of air pockets during high-performance driving. Precision-Machined External Bungs and Fittings: Ensure a perfect fit for factory hose connections. Kit Includes:

Turner Motorsport Aluminum Expansion Tank Performance Silicone Coolant Overflow Hose Aluminum Coolant Bleeder Screw Ball Stud 6mm Fitting Expansion Tank Cap Coolant Level Sensor Product Development:

Our Heavy Duty Aluminum Expansion Tank was designed, engineered, tested, and quality inspected by our Research & Development team. Our development process includes leading-edge product technology: FARO laser scanning for reverse engineering and quality inspection, SolidWorks 3D CAD modeling, rapid prototyping utilizing our in-house 3D printer, and rigorous long-term product testing.

Installation:

To aid in the installation process, we've assembled a start-to-finish installation guide, including detailed instructions on removing your factory cooling expansion tank and associated components.

Click HERE for Installation Instructions

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

The thermostat regulates the temperature of your coolant. At a predetermined temperature the thermostat will open to let coolant flow to the radiator and be cooled by airflow or the fan. Over time the thermostat will become stuck open or closed, leading to a variety of issues. A closed thermostat will never allow the coolant to reach the radiator and be cooled. Hot coolant will continue to circulate through the engine and absorb even more heat until boiling and the system overheats. An open thermostat is not as bad but is still not ideal - the coolant is always cool, with the temp needle always reading in the cool range. This tells the ECU to richen the fuel mixture to bring the car up to normal operating temp. So your fuel mileage decreases and the car runs rich.   

Replacing the thermostat is an easy but messy job. This thermostat includes the main o-ring (but a housing gasket may be required). Consider replacing the housing and any associated temp sensors while you're in there. The cooling system will need to be bled after.  

For vehicles with plastic thermostat housing 

Tired of dealing with brittle, dry-rotted rubber hoses? Whether you're refreshing your cooling system or replacing aging components, this ECS Silicone Radiator Coolant Hose Set is the ultimate upgrade. Designed for durability, performance, and a factory-perfect fit, these premium silicone hoses outperform standard rubber in every way.

Why Choose Silicone Over Rubber?

Made from heavy-duty, reinforced 4-ply fluorosilicone, ECS hoses withstand extreme temperatures and pressures far beyond OEM rubber hoses. Engineered to resist oil, fuel, and electrochemical degradation, these hoses are tested for continuous operation at 250°F and over 45 psi, delivering superior reliability, reduced turbulence, and improved coolant flow.

Key Benefits:

Direct OE Fitment – Perfectly molded to factory specifications for seamless installation.
Enhanced Durability – Heat-resistant silicone prevents cracking, swelling, and deterioration over time.
Superior Cooling Performance – Smoother internal passageways improve coolant flow and system efficiency.
Premium Hardware Included – Comes with German-style stainless steel worm-drive hose clamps for a secure fit.
Kit Includes:

Upper Radiator Hose
Lower Radiator Hose
Stainless Steel Worm-Drive Hose Clamps (4)
Replaces OEM Part Numbers: 17127599450 & 17127540127. Can be used with your factory connectors.

Introducing Mishimoto's Universal Oil Cooler (19 row with Thermostat)

In pursuit of optimal engine lubrication, even under ideal driving conditions, is paramount for BMW owners. Elevated oil temperatures can compromise oil pressure and hinder efficient lubrication. Turner Motorsport's new oil cooler offers a solution to maintain cool oil temperatures, ensuring your engine functions at its best. This comprehensive kit includes four feet of stainless braided line, adapter fittings, and an oil filter sandwich adapter.

Key Features:

• Effective Heat Dissipation: The oil cooler efficiently dissipates heat, keeping oil temperatures within the optimal range for peak engine performance.
• Comprehensive Kit: This kit includes four feet of stainless braided line, adapter fittings, and an oil filter sandwich adapter, providing everything you need for a seamless installation.
• Precise Temperature Control: Equipped with a thermostat for fine temperature and flow control, ensuring the ideal oil temperature is maintained.
• Proposition 65 Compliant: This product complies with Proposition 65, a California law that ensures product safety.

Elevate your BMW's engine performance and protect it from the effects of elevated oil temperatures. Turner Motorsport has the solution you need.

WARNING! Prop 65 may apply to this product.

Proposition 65 (Safe Drinking Water and Toxic Enforcement Act of 1968) is a California law that applies to all companies selling products in California. Prop 65 requires any listed chemical present above very low levels that are known to cause cancer, birth defects, or other reproductive harm.

For more information about California Prop 65 warning, see: www.P65Warnings.ca.gov.