Select Vehicle
BMW
Mini
Create an account to be able to build Wish Lists.
This product was last offered at the strikethrough price on
06-15-2026
This product was last offered at the strikethrough price on
06-15-2026
BMW N54 N55 S55 Mosselman Thermostat Installation Kit is designed to ensure a seamless installation of the Mosselman thermostat on BMW engines. This comprehensive kit from Turner Motorsport includes all necessary gaskets and components, guaranteeing a reliable and precise installation for optimal engine performance.
Upgrade your BMW's cooling system with the Mosselman Thermostat Installation Kit from Turner Motorsport, ensuring a top-quality, reliable setup for your engine.
This product was last offered at the strikethrough price on
05-03-2026
This product was last offered at the strikethrough price on
05-03-2026
If your vehicle is experiencing cooling issues, chances are the thermostat is the cause. Common symptoms include prolonged warm-up at highway speeds from the thermostat being stuck open, or consistent overheating issues from the thermostat being stuck in the closed position. Either condition can result in poor performance, and potential damage to vital components in your vehicle.
Kit includes
This item fits the following BMWs:
2008-2013 E82 BMW 135i 135is 1M Coupe
2013+ E84 BMW X1 xDrive35i
2011 E90 BMW 335i 335xi 335i xDrive - Sedan
2011-2013 E92 BMW 335i 335xi 335i xDrive - Coupe
2011-2013 E93 BMW 335i Convertible
2011-2013 E70 BMW X5 xDrive35i
2011-2013 E71 BMW X6 xDrive35i
This product was last offered at the strikethrough price on
05-03-2026
This product was last offered at the strikethrough price on
05-03-2026
Just like the rest of your vehicle's major systems, the cooling system must also be addressed periodically to ensure proper cooling and component reliability. Plastic and rubber components become brittle and prone to splitting or cracking after long periods of heating and cooling cycles, especially in colder climates! The coolant itself can degrade or become contaminated, leading to potential corrosion or freezing issues. Finally, thermostats and sensors can fail completely, preventing proper cooling and/or coolant temperature readings to become inaccurate.
To make sure you are not left stranded on the side of the road with an overheated engine, we have put together this Basic Cooling System Service kit. This kit contains all of the most-likely-to-fail components, giving you peace of mind knowing your engine will continue to run cool for another 60,000+ miles.
See kit contents below for all included components.
This product was last offered at the strikethrough price on
06-14-2026
This product was last offered at the strikethrough price on
06-14-2026
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
This product was last offered at the strikethrough price on
06-14-2026
This product was last offered at the strikethrough price on
06-14-2026
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.
The water pumps in these BMW models are known for failure near 80,000 miles is a very common issue often times leaving the owner stranded. This kit provides a single stop for water pump and thermostat replacement needs to save the search and get you back on the road.
Kit includes:
This product was last offered at the strikethrough price on
06-13-2026
This product was last offered at the strikethrough price on
06-13-2026
This product was last offered at the strikethrough price on
05-03-2026
This product was last offered at the strikethrough price on
05-03-2026
Due to weak rubber and plastic construction, vital cooling system parts are prone to premature failure. Key components, such as radiator hoses, the thermostat, and the expansion tank are particularly prone to cracks, leaks, and catastrophic failure, which can lead to overheating and potentially severe engine damage. Fortunately, our team of experts has assembled this kit of high-performance alternatives and high-quality OE replacement components, both tailored to safeguard your cooling system from failure and increase cooling system capability.
The Turner Motorsport Level 1 Performance Cooling System Refresh Kit is the ultimate solution for ensuring long-term reliability and enhanced cooling performance. Each component in this comprehensive kit has been carefully selected by our team of enthusiasts to address common failure points and provide a robust, performance-oriented upgrade for your vehicle. By replacing aging factory parts with premium, high-performance alternatives, you’ll optimize cooling efficiency and safeguard your engine from the stress of overheating.
Our comprehensive "Level 1" High-Performance Cooling System Service Kit includes:
Turner Motorsport Heavy Duty Aluminum Expansion Tank Pierburg Full Aluminum Water Pump ECS Aluminized Water Pump Hose V2.0 Bremmen Parts Thermostat ECS Performance Silicone Radiator Hose Kit Genuine BMW Blue G48 Antifreeze (2 Gallons) Redline Water Wetter (12 oz.)
This product was last offered at the strikethrough price on
04-01-2026
This product was last offered at the strikethrough price on
04-01-2026