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BMW Cooling System Parts & Accessories for BMW 5 Series E39 (1996-2003)

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The cooling system is arguably the weakest point in numerous BMWs. If you drive an aging BMW or plan on taking your car to the track like we do, we recommend beefing up your cooling system before going to the track. Generally, the main components in your cooling system that are prone to failure include the following: expansion tank, factory hoses, water pump, thermostat, fan (especially if your vehicle comes factory with a clutch fan), and radiator. Factory BMW expansion tanks are plastic and prone to either breaking off at connection points or combusting. As factory rubber hoses age they either crack or break over time - we offer silicone cooling hose upgrades for most applications to avoid future failures. If you have an older vehicle, your water pump likely comes from the factory with a plastic impeller - we offer upgraded water pumps with metal impellers that are far more reliable. Newer model BMWs utilize electric water pumps - BMW spent millions of dollars engineering these water pumps, but they fail so often that we recommend replacing at 60,000 mile service intervals to avoid being stranded on the side of the road. In terms of thermostats, we offer various upgraded thermostats for racing applications. If your BMW utilizes a clutch fan from the factory, we have several options available in terms of universal electric fans - we recommend replacing these to avoid sending brittle plastic fan blades through your hood. For radiators, we recommend swapping out your radiator for one that does not use plastic connection points like your factory radiator.

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Bav Auto Thermostat With Aluminum Housing - M52TU M54

For vehicles with production date from 09/1998

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T#:12544802

Part#: 11531437040

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$ 84.99 USD

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The plastic thermostat cover in your BMW is a known point of failure. Throughout years of repeated contact with hot coolant, the plastic can crack and cause massive coolant leaks and potential overheating. Eliminate one of the weak links in your cooling system with a replacement aluminum thermostat housing. By installing this aluminum unit, you have no worries as far as plastic housing cracks go

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Bav Auto Coolant Expansion Tank - E36 E39 Z3 M50 M52 S50 S52 ...

For vehicles with production date up to 08/1998

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T#:638094

Part#: 17111723520

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$ 31.99 USD

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Replace your old expansion tank to prevent potential failure or leaks. Includes a brand new coolant level sensor. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.

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Schwaben Coolant Refill/Air Purge Tool

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T#:362940

Part#: 003466SCH01

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$ 87.99 USD

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When it comes to BMW's we all know the weak point is commonly in the cooling system, many models proving hard to bleed the air pockets out after the refresh. The coolant refill tool solves this problem, ensuring that you get an air pocket free fill. The entire task is as simple as draining the system like normal, reinstalling the drain plugs and hooking the tool up to your refill location. The reason this tool works so well is due to the venturi valve, it converts air pressure from the compressor to vacuum inside the cooling system, then with a twist of a valve sucks coolant right into the system using the vacuum pressure.

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Coolant Vacuum Purge & Refill Tool Set

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T#:402498

Part#: 024948SCH01A

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$ 86.99 USD

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The Schwaben Coolant Vacuum Fill Tool ensures no air pockets get into your cooling system while you're replacing your coolant - intended for use to refill your cooling system, not for removal. Can be used with Schwaben fluid extractors or with shop air - standard air compressor with a minimum rating of 90 PSI (6.2 bar). Includes all fittings and adapters necessary for use, with a molded storage case to keep your Schwaben Vacuum Fill Tool pristine for future use.

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Bav Auto Heater Inlet Pipe - E46 E39 E53 E83 E85 Z3

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T#:638080

Part#: 11531705210

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$ 32.79 USD

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This is the plastic heater inlet pipe that connects the cylinder head to the heater inlet on cars with the M52 or M54 engine. The plastic on this hose becomes brittle over time and eventually leads to failure. Replace yours with a brand new Bav Auto Heater inlet pipe to prevent catastrophic failure.

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Bavarian Autosport Water Pipe - E46 E39 Z4 Z3 (M52TU, M54)

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T#:638085

Part#: 11537502525

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This plastic water pipe is positioned directly underneath your intake manifold. Due to its plastic construction, it is notorious for catastrophic failure. Rapid cooling loss and overheating are both direct results of this failure, posing permanent and lasting damage to the engine.

Replace your cracked/broken coolant pipe with this high-quality Bavarian Autosport component to ensure long-term reliability and perfect fitment.

From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.

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Schwaben Water Pump Pulley Holder for Removal of Fan Clutch

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T#:362357

Part#: 001170SCH01A

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Replacing the fan clutch on most BMW models requires holding the water pump pulley while removing the fan clutch lock nut. With less than 1 1/2" clearance on some models this project can easily turn into a mechanical nightmare. Using our special slim line fan clutch wrench in conjunction with the appropriate pulley spanner, the removal and installation required only a few moments.

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Schwaben Locking Hose Clamp Pliers

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T#:377131

Part#: 004170SCH01A

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$ 28.79 USD

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These pliers feature a spring loaded clamp with a 24" cable and will lock onto the clamp and hold open for easy removal. These pliers are designed to remove metal or plastic self-tightening hose clamps with diameters from 11/16" to 2-1/2" ( 18 to 54mm).

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Radiator Pressure Tester Kit

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T#:391482

Part#: 014710SCH01A

Ships on Jul 30, 2026

Sale - Save 25% $ 205.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 154.49 USD

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Are you refreshing your coolant system or having issues with coolant loss? An easy way to test your system for leaks and ensure you're able to maintain pressure without coolant loss is the Schwaben Cooling System Pressure Tester Kit.

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Schwaben Long-Reach 32mm Open End Fan Clutch Wrench

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T#:378938

Part#: 007701SCH01A

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$ 32.24 USD

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This tool was specifically designed for the tight clearances needed to remove most BMW fan clutches. Its slim design lets it fit into tight areas, and the extra-long length is ideal for fan shroud clearance.

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Schwaben Locking Hose Pinch-Off Pliers

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T#:379950

Part#: 009787SCH01A

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$ 33.99 USD

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Schwaben Locking Hose Pinch-Off Pliers have adequate clamping force to effectively seal large or pressurized cooling system hoses. These pliers are ideal for clamping shut most hoses, ensuring reliability in your automotive tasks. With swivel jaws, they provide even clamping force, making them a versatile tool for various applications.

Adequate clamping force for large or pressurized hoses
Ideal for clamping shut most hoses
Swivel jaws ensure even clamping force
Versatile tool for automotive maintenance

WARNING: This product contains chemicals known to the state of California to cause cancer, birth defects, and/or reproductive harm. For more information, visit http://www.p65warnings.ca.gov.

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Schwaben & Bav Auto Water Pump And Fan Clutch Tool Kit

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T#:375872

Part#: 001170SCH01AKT

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$ 49.49 USD

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Replacing the fan clutch on most BMW models requires holding the water pump pulley while removing the fan clutch lock nut. With less than 1 1/2" clearance on some models this project can easily turn into a mechanical nightmare. Using our special slim line fan clutch wrench in conjunction with the appropriate pulley spanner, the removal and installation required only a few moments.

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Schwaben 32mm / 36mm Fan Clutch and Oil Filter Cap Open-End Wrench ...

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T#:361021

Part#: DO-3236

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$ 19.49 USD

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Why buy two tools when you can get one that will do many jobs like this open end wrench? It is great for removing and installing the fan clutch and plastic oil filter cap. Also works great for removing and installing the VAN0S solenoid on M50 engine family. Use the same tools the Turner Motorsport tech's use!

Features:

Made of Chrome Vanadium Steel for strength
32/36mm open end sides

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Bav Auto Coolant Temperature Sensor - M52/S52, M62, M73, M54, S62 ...

Located on water pump housing For vehicles with production date from 09/1998

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T#:639828

Part#: 13621703993

Ships on Oct 7, 2026

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$ 16.79 USD

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This is the coolant temperature sensor used in many BMW models from the mid-1990s to the mid-2000s. The engine computer relies on the coolant temp to set the fuel mapping for the engine. As the car warms up the computer changes the fuel mixture. If your car is running a bit rich (too much fuel) it could be because this sensor is failing and not sending the correct info to the computer. This sensor is located in a variety of places depending on the engine. But it's one of those easy replacement items 'while you're in there' when doing a water pump or thermostat replacement. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.

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Bav Auto Coolant Level Sensor - BMW E36 E39 M50/52 S50/52

For vehicles with production date up to 09/1998

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T#:639793

Part#: 61318360855

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$ 16.99 USD

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This is the sensor / sending unit that notifies the computer if your coolant level is low. When this fails, it can give a false indication of low coolant -- or worse, not inform you of a low coolant situation that could potentially cause overheating. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.

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Bav Auto Expansion Tank Cap - E36 E46 E34 E39 E32 E38 E65 X3 X5 Z4 ...

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T#:640208

Part#: 17117639022

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This product was last offered at the strikethrough price on
06-03-2026

$ 11.89 USD

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This radiator expansion tank cap is used most BMW's from 1991-2006. It is a common failure item. When this item fails, it cannot hold pressure which results in your BMW overheating. If you are overhauling your coolant system, now is the time to consider preventative replacing this cap. It is also referred to as the coolant reservoir cap. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.

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Schwaben Radiator/ Intercooler Fin Comb

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T#:384260

Part#: 015326SCH01A

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$ 14.99 USD

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Straighten bent fins in heat exchangers like radiators, condensers, and intercoolers obstruct air flow and reduce heat transfer. Paper-thin fins are easily bent, even by slight pressure.

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