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

Track-tested and street-ready. the ULTIMATE cooling system upgrade for your N54 or N55!

Ditch your failure-prone plastic end tanks and increase cooling capacity by 25%, all without modifying your core support or accompanying shrouds. The CSFxTurner Performance Triple-Pass Radiator is the best cooling system upgrade for your N54/N55-equipped BMW!

The BMW 135i and 335i deliver serious performance straight from the factory, thanks to the twin-turbocharged N54 and single-turbo N55 engines. With strong midrange torque, high-revving capabilities, and proven tuning potential, these engines punch well above their weight. However, while the powertrain excels, the factory cooling system often falls short, especially under sustained boost or track conditions. Heat soak, rising coolant temps, and long-term thermal stress are common issues for enthusiasts pushing their N54 or N55 hard, making a performance radiator an essential upgrade for reliability and consistency.

Recognizing the critical need for increased cooling capacity, the team at Turner Motorsport partnered with CSF Race, world leaders in high-performance cooling systems with over 50 years of experience. The result is an Upgraded Performance Radiator: a high-performance, motorsport-grade upgrade engineered to keep your N54/N55 cooler and on the track for longer.

Design:

CSF-Exclusive "B-Tube" Technology
Unlike conventional "O-tube" designs, CSF’s patented "B-tube" structure increases wall strength while creating a more efficient flow path. This alone accounts for a 15% increase in cooling capacity over an OE "O-tube" radiator!
Dual Core Design
2-Row 42mm Core (Dual Core) Featuring CSF's Exclusive B-Tube Technology
Two-Row Compact Structure
This radiator was designed with precise fitment in mind. While total tube count and size are increased, the overall radiator dimensions stay the same as OE, ensuring a drop-in fit with zero modifications required.
25% Increase in Cooling Capacity
All of the above design features translate to a massive 25% cooling increase over the stock radiator!
FEATURES & BENEFITS

Direct-fit upgrade, no modifications required!
Accepts all OEM attachments via CNC-machined "Quick-Connect" hose ends and accessory mounting provisions
TIG-welded aluminum construction provides increased durability
An all-aluminum drain plug replaces the weak OE plastic unit, ensuring seamless functionality for the life of the radiator
Increased cooling efficiency for high-performance and racing use
Aluminum drain plug
Designed and tested by Turner Motorsport in collaboration with CSF Race
Backed by the Turner Lifetime Replacement Program
Every unit features precision CNC-machined brackets and OE-style connections for a seamless, drop-in installation using factory or aftermarket hoses. Whether you're building a track weapon or a high-horsepower street car, this Turner x CSF radiator is the cooling solution your N54 or N55 needs to perform reliably under pressure. All backed by the Turner Lifetime Replacement Program.

Ensure your BMW's engine performs at its peak with the installation of this highly efficient oil cooler from Mishimoto. Even in ideal driving conditions, elevated oil temperatures can lead to decreased pressure and compromised engine lubrication. This comprehensive kit includes four feet of stainless braided line, adapter fittings, and an oil filter sandwich adapter, all meticulously designed to reduce oil temperatures and uphold optimal driving circumstances.

• Rows: 19
• Overall Dimensions: 13" x 5.5" x 2"
• Core Dimensions: 11.25" x 5.5" x 2"
• Braided Hoses: 4ft .75 inch & 4ft 9 inch
• Braided Hose Fittings: -10AN
• Sandwich Plate Fittings: -10AN

Please take into consideration that this product may be subject to Proposition 65 (Safe Drinking Water and Toxic Enforcement Act of 1968). Proposition 65 is a California law that applies to companies selling products in California and necessitates the disclosure of chemicals known to cause cancer, birth defects, or other reproductive harm when present at levels exceeding specified thresholds. For further information regarding California Prop 65 warnings, visit www.P65Warnings.ca.gov.

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.

BMW Mishimoto 12" Universal Curved Blade Electrical Fan

The BMW Mishimoto 12" Universal Curved Blade Electrical Fan is an ideal upgrade for enhancing cooling efficiency or addressing fitment issues with aftermarket components. Turner Motorsport offers this fan with a slim profile that allows for easy installation flush against the radiator, ensuring optimal performance and space utilization.

Benefits:

• High-Flow Performance: Delivers 1150 CFM of airflow for superior cooling efficiency.
• Universal Fitment: Designed to fit a wide range of vehicles and applications.
• Compact Design: With a diameter of 12" and an overall thickness of just 2.5", it increases engine bay space and allows for flexible installation.
• Versatile Operation: Easily reversible for use as either a pusher or puller fan.
• Mishimoto Lifetime Warranty: Backed by Mishimoto's lifetime warranty for peace of mind.
• Prop 65 Warning: Note that Proposition 65 may apply to this product. For more information, visit www.P65Warnings.ca.gov.