Product Details
Most modern BMWs are notorious for their cooling system issues, often leaving owners stranded or causing irreversible engine damage in the event of failure. At the heart of these issues is the coolant expansion tank—a crucial component responsible for holding hot engine coolant under high pressure. Unfortunately, BMW chose to manufacture the factory E46 M3 expansion tank out of plastic. After years of exposure to high temperatures and chemical-laden antifreeze, the plastic degrades, eventually weakening enough to rupture.
With this failure in mind, Turner's team of BMW enthusiasts set out to develop the ultimate solution for E46 M3 owners: a robust expansion tank built to last! Constructed from durable 5052 TIG-welded aluminum, this tank withstands high temperatures and pressures without deteriorating over time. Unlike the OEM molded plastic tank, Turner's alternative is not prone to cracking, leaking, or weakening. With Turner's Heavy Duty Aluminum Expansion Tank Kit, you'll never experience expansion tank failure again!
To ensure precise fitment, 3D CAD modeling was utilized to design an upgraded tank that installs just like the factory unit. All bungs, nipples, and fittings are precision-machined for a reliable seal with factory hose ends. Unlike other aftermarket coolant reservoirs, this tank retains the factory coolant capacity and features a laser-cut Turner logo plate at the top of the tank to provide an exact level for filling. Additionally, internal baffles were implemented to prevent fluid cavitation inside the expansion tank. This ensures air pockets are not introduced to the cooling system, and prevents false coolant level warnings during performance driving.
Designed for both high-performance builds and daily drivers, the tank features a premium wrinkle black powder coat for a sleek "OEM+" look. This durable finish goes beyond style—it prevents corrosion for long-lasting reliability. In addition to the expansion tank, this kit also features a silicone overflow hose, a high-quality level sensor, and an OE expansion tank cap to ensure a comprehensive cooling system service. Don't let the problematic factory expansion tank leave you stranded—upgrade your E46 M3 and drive with confidence!
FEATURES
- Durable 5052 TIG-Welded Aluminum Construction ensures long-term reliability and prevents expansion tank failure.
- A premium wrinkle black powder coat finish offers a show-ready "OEM+" appearance while preventing corrosion.
- A laser-cut aluminum Turner logo plate provides a clear and accurate fill level indicator.
- Unique internal baffles prevent the introduction of air pockets during performance driving.
- All external bungs and fittings are precision-machined to fit factory hose ends, providing a leak-free seal.
KIT CONTENTS
- Turner Motorsport Aluminum Expansion Tank
- Performance Silicone Coolant Overflow Hose
- Expansion Tank Cap
- Coolant Level Sensor
INSTALLATION
The team at Turner Motorsport has assembled a start-to-finish installation guide, including detailed instructions on removing your factory components. To learn more, click the PDF under the "INSTALLATION" tab above.
High-performance ignition kit for your S54 featuring spark plugs, Turner high-performance ignition coils, and dielectric grease to make sure you have no issues at your next maintenance interval!
Turner BMW ignition coils are designed with performance and efficiency in mind. An engine needs 3 main components to run (Air, Fuel, and Spark). Turner ignition coils are modified to increase energy output; more energy output results in a faster, more efficient, and consistent burn to make sure your fuel is being utilized to its maximum potential. These coils offered by Turner feature a blue housing that gives your engine the performance and aesthetic you're looking for. All Turner Ignition coils are backed by the lifetime replacement program.
Ignition coils should be changed every 40,000 - 60,000 miles and are an important maintenance item due to the essential part they play in your engine's health, performance, and efficiency. Choose Turner Ignition Coils to keep your engine running strong and healthy.
Features and Benefits:
- Increased performance
- New spark plugs and grease
- Direct fitment
- Signature Turner Blue ignition coils
- Backed by the lifetime replacement program.
Not for sale or use in the state of California on any pollution-controlled vehicle as per the California Air Resources Board.

Prop 65 Warning