Heavy Duty Aluminum Expansion Tank Kit - E46 M3 S54

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 E46 M3 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 E46 M3 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!

Heavy Duty Aluminum Expansion Tank Kit - E46 M3 S54
10X Entries Into Our F80 M3 Sweepstakes
T#:37014879
Part#: 008682LA02
In Stock
Sale - Save 20% $ 434.99

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

$ 347.99 USD
Free Shipping
Sale - Save 20%
$ 434.99

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

$ 347.99 USD
Free Shipping

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 E46 M3 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 E46 M3 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 E46 M3 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 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.

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High-Performance Cooling System Service Kit - Level 1
10X Entries Into Our F80 M3 Sweepstakes
T#:37622240
Part#: 008682LA02RF1KT
In Stock
$ 1,044.37 USD
Free Shipping on orders $49 and up

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 ECS Silicone Radiator Hoses Wahler Thermostat (80°C) Bremmen Aluminum Water Pump Bremmen Parts Auxiliary Fan Switch Genuine BMW Water Pump O-Ring Genuine BMW G48 Antifreeze (1 Gallon) Redline Water Wetter Performance Coolant Additive (12 oz.)

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High-Performance Cooling System Service Kit - Level 2
10X Entries Into Our F80 M3 Sweepstakes
T#:37622242
Part#: 008682LA02RF2KT
Ships on Dec 18, 2026
$ 1,215.85 USD
Free Shipping on orders $49 and up

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.

Our Level 2 High-Performance Cooling System Service 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 all-inclusive "Level 2" High-Performance Cooling System Service Kit includes:

Turner Motorsport Heavy Duty Aluminum Expansion Tank ECS Silicone Radiator Hoses ECS Aluminum Water Pump Pulley Wahler Thermostat (80°C) Bremmen Aluminum Water Pump Bremmen Parts Auxiliary Fan Switch Continental Accessory Belt ECS Kevlar-Reinforced A/C Compressor Drive Belt Genuine BMW Water Pump O-Ring Genuine BMW Water Pump Bolts Genuine BMW G48 Antifreeze (1 Gallon) Redline Water Wetter Performance Coolant Additive (12 oz.)

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Turner Motorsport Power Pulley Kit - E46 M3
10X Entries Into Our F80 M3 Sweepstakes
T#:340398
Part#: PPK-S54
In Stock
Sale - Save 20% $ 412.99

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

Starting at $ 330.39 USD
Free Shipping
Sale - Save 20%
$ 412.99

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

Starting at $ 330.39 USD
Free Shipping
Underdrive Power Pulleys work to 'free up' horsepower. Any accessory that spins from the main drive belt is using up power. That's power that could otherwise be used to move the car. By giving some of that power back to the engine, you can make the car faster! It's like FREE HORSEPOWER !

Underdrive pulleys for your BMW will slow down engine-mounted accessories - the water pump, power steering pump, and alternator*. These systems contribute to 'parasitic losses' - power lost from what the engine could produce if it did not have these systems. Since less energy is used to move them, that power is transferred back to the engine and used to propel the car. Our pulleys give a 10-20% reduction in rotation, releasing 10hp on the E46 M3. There's also a small but noticeable improvement in throttle response too! We have done extensive testing and development work, both on and off the track, to ensure that the accessory systems function as they should. On our Racing pulley kits we actually underdrive certain components more so we feel our Street pulleys are an ideal compromise between power/torque gains, reliability, and system performance. Our pulley kits have been on the market for over ten years, and used in all of our own cars, with zero component failures related to their use.

Our pulleys are made from T-6061 aluminum and finished in a durable black hard anodize that is very resistant to wear, chemical exposure, and heat. We designed our pulleys to look similar to the factory parts but also to be stronger and, in most cases, slightly lighter too. For example, a Turner alternator pulley is less than half the weight of the stock steel pulley! With our hardcoat aluminum you will never have to worry about a serious failure of a stock plastic pulley. A 'stealth' approach to aesthetics was our goal and we let the results speak for the pulley design. Installation is straight forward and easy with simple hand tools. Removal of the fan is required for access to the front of the engine. Total install time for a 3-piece pulley set should be around 1.5 hours. A new longer belt is included and we also recommend replacing the separate A/C belt, belt tensioners, and the guide and deflection pulleys at the same time.

* Alternator Pulley Options
Stereo Systems. We offer our kits in two different ways: the full Power Pulley Kit with all 3 pulleys or a 2 pulley kit if you do not wish to underdrive your alternator (for large stereo systems or other battery-draining modifications). Our kits have been tested for compatability with the factory premium stereo systems (Harmon Kardon, etc). But any major alterations or upgrades from the factory system will work best with our 2 pulley kit and no underdriving of the alternator. For all stock stereo systems the 3 pulley set is recommended because the Turner alternator pulley will help make more power and is also much lighter than the stock pulley.

Additional Info
ClickHere for example Dyno Chart

Click here for installation instructions.


This underdrive pulley kit fits the following BMW:
2001-2006 E46 M3 coupe & convertible
2001-2002 MZ3 Z3 M Roadster / Z3 M Coupe (S54 engine)
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T#:637722
Part#: MMFS-E46-01K
In Stock
$ 460.99 USD
$ 460.99 USD
The Mishimoto electric fan uses a 16" slim profile electric fan that flows at 1,850 cubic feet per minute (CFM). The shroud and frame are black powedercoated steel and mounts to existing points on the radiator for a seamless install. Mishimoto has confirmed fitment with stock radiators as well as their own Performance and X-Line aluminum radiators. Hardware and instructions are included. Includes Controller & Sensors.
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