BMW Cooling System Parts & Accessories for BMW E90 M3 S65 4.0L

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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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Goldenwrench Supply Co - Corporate Logo
T#:641289
Part#: FXXCET-R
In Stock
$ 65.00 USD
Free Shipping
$ 65.00 USD
Free Shipping
Give the plain plastic factory coolant caps an upgrade with the brand new BLACKLINE Performance Coolant Expansion Tank Cap Cover from Goldenwrench. Each cap is CNC formed from T6 Aluminum and anodized in a limited release race inspired red color. All logos and decorations are finalized through a precision 3D milling process, machined into each cap for the ultimate premium finish. The BLACKLINE Performance Billet Coolant Expansion Tank Cap Cover will fit most BMW vehicles equipped with the N55, S55, S63, and S65 engine with the large coolant tank found in the following vehicles E90/E91/E92 M3 LCI, F22 M235i, F87 M2/M2 Competition, F80 M3, F82 M4, F10/F90 M5, and more (check your coolant cap ensuring that it is the same shape as seen in the product photos). Each kit comes with a Billet Coolant Expansion Tank Cap Cover, and an Installation Instruction Card. This is a not a full cap replacement. The Billet Cap Cover affixes to the top of your factory coolant cap installing easily in minutes.
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Goldenwrench Supply Co - Corporate Logo
T#:5691129
Part#: FXXCET-B
In Stock
$ 65.00 USD
Free Shipping
$ 65.00 USD
Free Shipping
Give the plain plastic factory coolant caps an upgrade with the brand new BLACKLINE Performance Coolant Expansion Tank Cap Cover from Goldenwrench. Each cap is CNC formed from T6 Aluminum and anodized in a limited release race inspired blue color. All logos and decorations are finalized through a precision 3D milling process, machined into each cap for the ultimate premium finish. The BLACKLINE Performance Billet Coolant Expansion Tank Cap Cover will fit most BMW vehicles equipped with the N55, S55, S63, and S65 engine with the large coolant tank found in a variety of M vehicles(check your coolant cap ensuring that it is the same shape as seen in the product photos). Each kit comes with a Billet Coolant Expansion Tank Cap Cover, and an Installation Instruction Card. This is a not a full cap replacement. The Billet Cap Cover affixes to the top of your factory coolant cap installing easily in minutes.
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Vargas Turbo Technologies - Corporate Logo
T#:7530036
Part#: COOLANTCAPBLUE
In Stock
$ 79.99 USD
Free Shipping
$ 79.99 USD
Free Shipping
VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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Vargas Turbo Technologies - Corporate Logo
T#:7530034
Part#: COOLANTCAPRED
In Stock
$ 79.99 USD
Free Shipping
$ 79.99 USD
Free Shipping
VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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Race German - Corporate Logo
T#:6827887
Part#: RGCTSAM12
In Stock
$ 35.99 USD
Free Shipping on orders $49 and up
Race German has devoted themselves to providing quality products for late model BMWs that cover both street and track applications. Race German has now grown their catalog to a wide variety of models and products geared towards keeping your car looking and running nice. For those looking to install an aftermarket coolant temp gauge, Race German has the perfect accessory for you! This adapter is machined out of aluminum and splices into your upper radiator hose. Perfect for use with Race German's E30 temperature gauge but has compatibility with a wire variety of other cars as well! Features: Tapped for M12x1.5 sized sensor 38mm diameter outlets which fit most BMW hoses Includes 2x hose clamps **Does not include temp sensor
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Race German - Corporate Logo
T#:6827888
Part#: RGCTSA1/8NPT
In Stock
$ 35.99

This product was last offered at the strikethrough price on
10-07-2026

$ 31.99 USD
Limited Qty Sale
Free Shipping on orders $49 and up
$ 35.99

This product was last offered at the strikethrough price on
10-07-2026

$ 31.99 USD
Limited Qty Sale
Free Shipping on orders $49 and up
Race German has devoted themselves to providing quality products for late model BMWs that cover both street and track applications. Race German has now grown their catalog to a wide variety of models and products geared towards keeping your car looking and running nice. For those looking to install an aftermarket coolant temp gauge, Race German has the perfect accessory for you! This adapter is machined out of aluminum and splices into your upper radiator hose. Perfect for use with Race German's E30 temperature gauge but has compatibility with a wire variety of other cars as well! Features: Tapped for 1/8NPT sized sensor 38mm diameter outlets which fit most BMW hoses Includes 2x hose clamps **Does not include temp sensor
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Goldenwrench Supply Co - Corporate Logo
T#:641288
Part#: FXXCET
In Stock
$ 65.00 USD
Free Shipping
$ 65.00 USD
Free Shipping
Give the plain plastic factory coolant caps an upgrade with the brand new BLACKLINE Performance Coolant Expansion Tank Cap Cover from Goldenwrench. Each cap is CNC formed from T6 Aluminum and anodized with an Anthracite Gray color to compliment the factory engine cover. All logos and decorations are finalized through a precision 3D milling process, machined into each cap for the ultimate premium finish. The BLACKLINE Performance Billet Coolant Expansion Tank Cap Cover will fit most BMW vehicles equipped with the N55, S55, S63, and S65 engine with the large coolant tank found in the following vehicles E90/E91/E92 M3 LCI, F22 M235i, F87 M2/M2 Competition, F80 M3, F82 M4, F10/F90 M5, and more (check your coolant cap ensuring that it is the same shape as seen in the product photos). Each kit comes with a Billet Coolant Expansion Tank Cap Cover, and an Installation Instruction Card. This is a not a full cap replacement. The Billet Cap Cover affixes to the top of your factory coolant cap installing easily in minutes.
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VTT Billet Coolant Reservoir Cap - Anodized Clear - Most BMWs 2006+ (...
This coolant cap retains ALL of the factory provisions by simply allowing you to snap t...
2X Entries Into Our F80 M3 Sweepstakes
Vargas Turbo Technologies - Corporate Logo
T#:7530035
Part#: COOLANTCAPRAW
Ships in 3 Business Days
$ 78.99 USD
Free Shipping
$ 78.99 USD
Free Shipping
VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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AUTOTECKNIC - Corporate Logo
T#:39497984
Part#: BM-0803-GC
In Stock
$ 74.99 USD
Free Shipping on orders $49 and up
Turner Motorsport offers the AutoTecknic Dry Carbon Coolant Expansion Tank Cap Cover - Gloss Carbon as the perfect addition for BMW owners looking to elevate their engine bay’s appearance with premium materials and precision engineering.
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Rogue Engineering - Corporate Logo
T#:13694122
Part#: RADE9X-M3-ONLY
Ships in 9 Business Days
$ 79.00 USD
Free Shipping on orders $49 and up
Benefits of Rogue Engineering Silicone Radiator Hoses More resistant to high temperatures, solvents and oil, when compared to OEM rubber hoses. Temperature ranges from -149° F to 500° F, much larger range than OEM (typical range for OEM is -40o F to +275o F) Our hoses can handle more pressure, with a maximum pressure of 350psi. Our silicone hoses stay flexible, whereas rubber can harden and crack over time. Available only in BLACK color, with discrete RE logo. All Rogue Engineering Silicone Radiator Hose kits come complete with new, replacement hose clamps as the factory ones are not suitable for reuse after long years of service. Application Notes The E9X M3 kit replaces 11537838214 and 11537840661 and fits the following: 2008-2013 E9X M3 (US and Euro) Notes: The E9X M3 hose kit requires the use of OEM connectors from the original hoses.
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Vargas Turbo Technologies - Corporate Logo
T#:7530033
Part#: COOLANTCAPBLK
In Stock
$ 79.99 USD
Free Shipping
$ 79.99 USD
Free Shipping
VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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Vargas Turbo Technologies - Corporate Logo
T#:52164954
Part#: S65COOLHEATBLK
Ships in 10 Business Days
New Item
$ 127.99 USD
Free Shipping
$ 127.99 USD
Free Shipping
Upgrade your BMW M3’s engine bay while simultaneously reinforcing your cooling system with the VTT Billet/Silicone Heater Return Pipe Hose.


Vargas Radiator Hose Kit - Black - BMW E9X M3
2X Entries Into Our F80 M3 Sweepstakes
Vargas Turbo Technologies - Corporate Logo
T#:52164958
Part#: S65RHKBLK
Back Ordered
New Item
$ 314.99 USD
Free Shipping
$ 314.99 USD
Free Shipping
The VTT S65 Radiator Hose Kit is the premier cooling system upgrade for the BMW E9X M3.
Vargas Lower Radiator Hose - Black - BMW E9X M3
2X Entries Into Our F80 M3 Sweepstakes
Vargas Turbo Technologies - Corporate Logo
T#:52164955
Part#: S65COLLOWBLK
Ships in 10 Business Days
New Item
$ 179.99 USD
Free Shipping
$ 179.99 USD
Free Shipping
Designed for the S65 V8 engine, the VTT Lower Radiator Hose upgrade addresses the common maintenance headaches associated with aging BMW cooling systems.
Vargas Upper Vent Hose - Black - BMW E9X M3
2X Entries Into Our F80 M3 Sweepstakes
Vargas Turbo Technologies - Corporate Logo
T#:52164960
Part#: S65COUVHBLK
Ships in 10 Business Days
New Item
$ 74.99 USD
Free Shipping
$ 74.99 USD
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This VTT kit provides a permanent fix by utilizing heavy-duty silicone and anodized billet aluminum ends.

Vargas Water Pump Vent Hose - Black - BMW E9X M3
2X Entries Into Our F80 M3 Sweepstakes
Vargas Turbo Technologies - Corporate Logo
T#:52164956
Part#: S65COPUBLK
Ships in 10 Business Days
New Item
$ 104.99 USD
Free Shipping
$ 104.99 USD
Free Shipping
Prevent a roadside breakdown with the VTT Billet/Silicone S65 Water Pump Vent Hose, the ultimate maintenance upgrade for your BMW E9X M3.

Vargas Coolant Hose Upgrade Kit - Black - BMW E9X M3
2X Entries Into Our F80 M3 Sweepstakes
Vargas Turbo Technologies - Corporate Logo
T#:52164951
Part#: S65COOLFULLBLK
Ships in 10 Business Days
New Item
$ 524.99 USD
Free Shipping
$ 524.99 USD
Free Shipping
Upgrade your BMW E9X M3’s engine bay and cooling reliability simultaneously with the Vargas Turbo Technologies S65 Billet/Silicone Full Hose Kit.
Vargas Upper Radiator Hose - Black - BMW E9X M3
2X Entries Into Our F80 M3 Sweepstakes
Vargas Turbo Technologies - Corporate Logo
T#:52164959
Part#: S65COUPRABLK
Ships in 10 Business Days
New Item
$ 179.99 USD
Free Shipping
$ 179.99 USD
Free Shipping
The VTT Billet/Silicone Upper Radiator Hose is the only solution on the market that addresses both the hose material and the connector integrity simultaneously.