BMW Cooling System Parts & Accessories for BMW 3 Series E46 (1999-2005)

When it comes time to replace your thermostat, be sure you have everything you need. This kit includes everything you need to replace your thermostat, including the thermostat.

Kit includes:

• Thermostat
• Thermostat O-Ring
• 1.5 Liters of coolant

This item fits the following BMWs: 
2001-2006 E46 BMW M3 

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 3 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 3" High-Performance Cooling System Service Kit includes:

CSFxTurner Performance Triple-Pass Aluminum Radiator 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.)

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.

As the E46 M3 gets on in years and mileage, the cooling system will be one of the areas that needs the most attention. We have packaged all of the major cooling components into one overhaul kit:

• radiator
• water pump
• thermostat
• radiator hoses and clamps
• gaskets and o-rings

We have found that the E46 M3 can develop inconvenient cooling issues, even on daily driven street cars. While the infamous radiator and water pump failures of the E36 are a thing of the past, the E46 M3 still has its own complications. The best approach to avoid bigger problems is preventative maintenance. We recommend replacing the water pump before 80,000 miles and the radiator before 100,000 miles. By addressing these problem areas before a failure, you will save yourself a larger repair bill in the future.

In addition to the standard cooling package items above, there are several other cooling-related components that may make sense to do at the same time:

• Original BMW coolant
• fan clutch
• main serpentine belt and A/C belt
• Turner Power Pulley Kit (because now is the perfect time!)

This cooling overhaul package fits:
2001-2006 E46 BMW M3
 

This is a compete cooling system overhaul kit, which includes all the common cooling system failure parts bundled into a complete package. This cooling system package is for the E46 with the M52/54 engine.  

A failure in the cooling system can lead to overheating and catastrophic engine failure. Don't gamble your engine! By replacing these core items preventatively, such as the thermostat housing, radiator, and waterpump, you are defusing what could be a ticking cooling system time bomb. And if you've had a failure of one of these parts, now is the time to refresh your entire cooling system. Keep on top of the cooling needs of your engine for your own piece of mind. Potential buyers also see the upside of a properly maintained car with receipts. 

This cooling system overhaul kit fits the following BMWs: 
1999-2000 E46 3 Series Sedan/Wagon - 323i & 328i 
1999-2000 E46 3 Series Coupe/Convertible - 323Ci & 328Ci 
2001-2002 E46 3 Series Sedan/Wagon - 325i, 325xi, 330i, 330xi 
2001-2002 E46 3 Series Coupe/Convertible - 325Ci, 330Ci 

If you plan to drive your BMW aggressively on the track, it is important that you upgrade your cooling system to avoid overheating. To ensure your BMW keeps cool on the track, we have built out our new High Performance Cooling System Upgrade kits. Featured in this kit is everything you will need to redo your cooling system from top to bottom with OEM components, with select stock components swapped out for the high performance alternative! This kit includes a high performance Mishimoto Radiator, for significantly better cooling than the stock radiator and full aluminum construction that won't crack from long term heat cycling, a performance Mishimoto 70*C thermostat, for lower temperature operation and increased cooling of the engine, and a Stewart High Performance Water Pump, for dramatically increased coolant flow at all RPMs. 

Additional items included in this kit:

• OEM Replacement Coolant Hoses
• OEM Expansion Tank, Cap, and Level Sensor
• OEM Belts, Tensioners, and Pulleys
• OEM Auxiliary Fan Switch
• Genuine BMW Hardware for Easy Installation
• ECS Tuning Aluminum Water Pump Pulley - For increased reliability over the stock composite pulley

If you plan to drive your BMW aggressively on the track, it is important that you upgrade your cooling system to avoid overheating. To ensure your BMW keeps cool on the track, we have built out our new High Performance Cooling System Upgrade kits. Featured in this kit is everything you will need to redo your cooling system from top to bottom with OEM components, with select stock components swapped out for the high performance alternative! This kit includes a high performance Mishimoto Radiator, for significantly better cooling than the stock radiator and full aluminum construction that won't crack from long term heat cycling, a performance Mishimoto 70*C thermostat, for lower temperature operation and increased cooling of the engine, and a Stewart High Performance Water Pump, for dramatically increased coolant flow at all RPMs. 

Additional items included in this kit:

• OEM Replacement Coolant Hoses
• OEM Expansion Tank, Cap, and Level Sensor
• OEM Belts, Tensioners, and Pulleys
• OEM Auxiliary Fan Switch
• Genuine BMW Hardware for Easy Installation
• ECS Tuning Aluminum Water Pump Pulley - For increased reliability over the stock composite pulley

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.)

Take your BMW’s cooling system to the next level with this Turner Motorsport Cooling Upgrade Kit. Featuring a Heavy-Duty Aluminum Expansion Tank and a Mechanical Thermostat Conversion Kit, this combo is engineered to deliver ultimate reliability and superior performance for M52TU/M54 engines. Say goodbye to the cooling system failures common in stock setups—Turner Motorsport has you covered.

Turner Motorsport M52TU/M54 Heavy-Duty Expansion Tank Kit

The Turner Motorsport Aluminum Expansion Tank is a premium upgrade designed to replace the fragile factory plastic tank, which is known to crack, leak, or even explode. Crafted for durability, this tank’s all-aluminum construction with wrinkle black powder coating ensures this is the last expansion tank you’ll ever need.

Why Upgrade? The factory plastic tanks on BMW M52TU/M54 engines are notorious for failure under heat and pressure. Avoid the risk of being stranded on the side of the road with a mess of coolant—Turner Motorsport’s aluminum expansion tank is built to withstand years of demanding use and intense heat cycles.

Key Features and Benefits:

Complete Kit: Includes Turner Aluminum Expansion Tank, coolant level sensor, expansion tank cap, and flared coolant pressure release line. OEM Fit & Capacity: Direct fit with no modifications, maintains stock coolant capacity and expansion volume. Baffled Design: Prevents air pockets during aggressive driving and ensures accurate coolant level readings. Premium Construction: TIG-welded 5052 aluminum with machined fittings for factory hose compatibility. Turner Motorsport M52TU/M54 Mechanical Thermostat Conversion Kit

Replace your problematic factory plastic thermostat housing with Turner Motorsport’s high-quality billet aluminum Thermostat Conversion Kit. This upgrade not only provides increased reliability but also allows for thermostat swaps to suit specific temperature requirements, making it ideal for daily drivers and track cars alike.

Why Make the Switch? The factory plastic thermostat housing with its built-in thermostat is prone to cracking and requires the whole unit to be replaced during maintenance. Turner’s conversion kit changes the game by providing a durable billet housing with a replaceable thermostat for flexibility and lower maintenance costs.

Key Features and Benefits:

Increased Reliability: Uses an M50/S50 mechanical thermostat, including an 80°C thermostat for enhanced cooling control. Customizable: Includes barbed hose connections for standard E46 M3 hoses and -16 ORB connections for custom hoses. Engineered to Last: CNC-machined from billet 6061 aluminum and black anodized for corrosion resistance. Enhanced Sealing: Features a Viton gasket for superior durability and sealing performance. Kit Includes:

6061 Billet Aluminum Thermostat Housing 80°C Mechanical Thermostat Thermostat Housing Gasket Thermostat Harness ECS Silicone E46 M3 Cooling Hoses Turner Motorsport Precision Engineering & Product Development

Every component in this cooling upgrade kit has been rigorously designed, engineered, and tested by Turner Motorsport’s Research and Development team. Using state-of-the-art technology such as FARO laser scanning, SolidWorks 3D modeling, and in-house rapid prototyping, Turner ensures that these products meet the highest standards of quality, precision, and durability.

Upgrade your BMW with confidence—Turner Motorsport is your partner in performance and reliability.