Expansion Tanks

A BMW expansion tank ensures that your radiator is always full, even when cold, and provides a way for hot fluid to expand without releasing fluid on the road below you. Factory BMW tanks are made of plastic, and will eventually crack, leak and fail. BMW expansion tanks should be inspected during routine maintenance. We recommend replacing the expansion tank as a preventatively whenever you replace the radiator and coolant hoses. We also offer high-quality aluminum replacement tanks for some BMWs. Use our SEARCH BY MODEL feature to filter these items for your BMW.

Want to learn more about your BMW's cooling system? Check out our BMW cooling system tech page by clicking here.

Need help finding Expansion Tanks for your BMW? Call us at 877.639.9648, email us, or live chat for expert assistance.

Heater Pipe O-Ring - E46 323i/325i/328i/330i

Replacement o-ring for heater hoses and expansion tank

Price: $0.99

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Coolant Level Sensor O-Ring, CRP - E36 323i/325i/328i/M3, E34 525i, E39 528i/540i

O-ring to seal the level sensor in the expansion tank. OEM-type replacement for BMW part #61311361249.

Price: $1.99

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Expansion Tank/Coolant Bleeder Screw, Rein

Replace a stripped or broken radiator bleed screw. OEM-type replacement for BMW part #17111712788.

Price: $2.99

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Expansion Tank Cap - 17111468077

Aftermarket Replacement # 17 11 1 468 077, 24 Month Warranty

Price: $3.28
4.43

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Brass Radiator Bleeder Screw - Most BMWs

Never break your BMW bleeder screw again!

Price: $3.79
5.19

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Screw Plug for Coolant Expansion Tank - 17111707818 - E46,E53,E83,E85

Quality aftermarket drain plug for expansion tank on many E46, E83, E53, and E85/E86 models.

Price: $4.74
7.69

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Genuine BMW Isolator Grommet / Bump Stop - 13717542860

Genuine BMW # 13717542860

Price: $5.66

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Cooling System Plug, Rein - E60, F10, E63, F06/F13, F02

Blind plug used in a variety of places. OEM-type replacement for BMW part #11531436850.

Price: $5.99

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Expansion Tank Cap - 17132754264

Aftermarket Replacement # 17 13 2 754 264, 24 Month Warranty

Price: $6.05
8.28

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Coolant Expansion Tank Cap - E36, E46, E34, E39, E38, X3, X5, Z3, Z4

Keep optimum cooling performance - replace your cap every three years! Aftermarket replacement for BMW part #17117639022.

Price: $6.64
9.09

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Coolant Expansion Tank Cap, Aftermarket - E9X M3, E60 E63 F01 E70 E71

Keep optimum cooling performance - replace your cap every three years! High quality replacement for BMW part #17137516004

Price: $6.64
8.73

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Threaded Cap for Coolant Level Sender Delete - E30 E36

Original BMW threaded cap is great for deleting the coolant level sensor on track cars.

Price: $7.47
7.86

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Radiator Cap 1.4 Bar - E30 325e/325i & E34 525i M20 - 17111742232

This is a simple and budget-friendly replacement radiator cap made by a quality aftermarket manufacturer.

Price: $7.49
27.29

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Expansion Tank Cap - 17114379047

Aftermarket replacement cap coolant reservoir on E28 828e, E24 633CSi, and early E30 325e/i models.

Price: $7.99
28.93

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Charge Air Cooler Reservoir Cap - Many 2015+ Models

Keep optimum cooling performance - replace your cap every three years! Replacement for BMW part #17117639024

Price: $7.99

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Cooling System Plug, Rein - F3X, E60, F10, G30, E63, F06/F12/F13, F02, X5/X6

Blind Plug/Cap used in a variety of locations on coolant hoses and connectors.

Price: $7.99

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Expansion Tank Cap, CRP - 2002, E21, E12, E28, Big Coupe, E24, E23 735i, E26 M1

Keep optimum cooling performance - replace your cap every three years!

Price: $10.99
21.89

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Coolant Expansion Tank Cap, Aftermarket - E82, F22, E9X, F3X, F10, F13, G30, F01, F02, F25, F26, G01, G02, E70, F15, G05, E71, F16, G06

Keep optimum cooling performance - replace your cap every three years! Direct replacement for BMW part #17117639020.

Price: $10.99
13.00

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Expansion Tank Retaining Clip - 17111707777

Used to connect the expansion tank to the mount plate (against the radiator) on E46, E85 Z4 & X5 3.0 / M54 models

Price: $10.99
12.92

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Coolant Expansion Tank Cap, OEM - E36, E46, E39, E38, X3, X5, Z3, Z4

Keep optimum cooling performance - replace your cap every three years! OEM replacement for BMW part #17117639022.

Price: $11.24
21.36

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Expansion Tank Cap, Reutter - Many Vintage BMW Applications

High quality replacement radiator cap with a 24 Month Warranty

Price: $11.99
20.15

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Expansion Tank Cap, CRP - E30 325i, E34 525i M20

Keep optimum cooling performance - replace your cap every three years!

Price: $13.99
26.23

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Charge Air Cooler Reservoir Cap, BMW - Many 2015+ Models

Keep optimum cooling performance - replace your cap every three years! Genuine replacement for BMW part #17117639024

Price: $15.42
16.23

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Coolant/Washer Level Sensor (installs in expansion tank) - Many BMW (see list)

High Quality Replacement to BMW # 17137553919

Price: $15.99
28.84

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Coolant Expansion Tank Cap, Rein - E9X M3, E60 E63 F01 E70 E71

Keep optimum cooling performance - replace your cap every three years! OEM-type replacement for BMW part #17117639021.

Price: $17.99
24.70

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Coolant Expansion Tank Cap, Rein - E82, F22, E9X, F3X, F10, F13, G30, F01, F02, F25, F26, G01, G02, E70, F15, G05, E71, F16, G06

Keep optimum cooling performance - replace your cap every three years! High quality replacement for BMW part #17117639020.

Price: $17.99
23.44

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Coolant Level Sensor With Round Pins - E30 E34 E24 E32 (1987-1995)

Common cause of false warning light for coolant level

Price: $17.99
65.54

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Coolant Expansion Tank Cap, BMW - E82, F22, E9X, F3X, F10, F13, G30, F01, F02, F25, F26, G01, G02, E70, F15, G05, E71, F16, G06

Keep optimum cooling performance - replace your cap every three years! Original BMW part # 17117639020.

Price: $19.62
27.96

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Cap for Coolant Expansion Tank, BMW - G42 G20 G22 G26 G29

Original BMW cam for the main coolant reservoir on G42 2-series, G20 3-series, G22/G23/G26 4-series, and G29 Z4 models.

Price: $21.59
23.98

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Expansion Tank, Rein - E30 318i, E36 318i/318ti, E34 525i, Z3 1.9

Replacement coolant reservoir identical to the original BMW part #17111712835

Price: $21.99

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Coolant Expansion Tank Cap, BMW - G26 i4 e40/M50

Replacement pressure-regulating cap for the cooling system

Price: $22.58
27.96

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Expansion Tank Cap, Genuine BMW - E30 M3, E28 M5

Keep optimum cooling performance - replace your cap every three years! Genuine replacement for BMW part #17112227683

Price: $23.67
24.92

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Auto Transmission Cooler Thermostat, Rein - E46, E83 X3, E53 X5, E85/E86 Z4

OEM-type thermostat to regulate transmission cooler. Replaces BMW part #17111437362.

Price: $24.90
101.55

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Coolant Expansion Tank - E30 / E36 / Z3 4 cylinder, E34 525i - 17111712835

Replacement for your aged or damaged expansion tank

Price: $24.99
102.47

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Expansion Tank - 17111712835 - E36 / Z3 4-Cylinder and E34 525i

Aftermarket Replacement # 17 11 1 712 835, 24 Month Warranty

Price: $27.30
36.30

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BMW Expansion Tank - 34321112399 - E10

High quality, 24 Month Warranty

Price: $29.99
98.41

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Expansion Tank - URO - 17111741167

Aftermarket Replacement to BMW # 17111741167 with a 24 Month Warranty

Price: $31.34
37.65

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Expansion Tank Threaded Cap, BMW - E30 325e/325i, E28 528e, E24 633CSi

OEM replacement cap coolant reservoir on E28 828e, E24 633CSi, and early E30 325e/i models.

Price: $31.83
33.51

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Coolant Expansion Tank - E32 735i Sedan (1988-1994)

Quality aftermarket coolant overflow reservoir for E32 735i sedan models.

Price: $33.56
43.19

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Expansion Tank Kit, Rein - E30 318i, E36 318i/318ti, E34 525i, Z3 1.9

Replacement coolant reservoir identical to the original BMW part #17111712835

Price: $33.99

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Expansion Tanks

Heater Pipe O-Ring - E46 323i/325i/328i/330i

Price: $0.99

Coolant Level Sensor O-Ring, CRP - E36 323i/325i/328i/M3, E34 525i, E39 528i/540i

Price: $1.99

Expansion Tank/Coolant Bleeder Screw, Rein

Price: $2.99

Expansion Tank Cap - 17111468077

Price: $3.28 4.43

Brass Radiator Bleeder Screw - Most BMWs

Price: $3.79 5.19

Screw Plug for Coolant Expansion Tank - 17111707818 - E46,E53,E83,E85

Price: $4.74 7.69

Genuine BMW Isolator Grommet / Bump Stop - 13717542860

Price: $5.66

Cooling System Plug, Rein - E60, F10, E63, F06/F13, F02

Price: $5.99

Expansion Tank Cap - 17132754264

Price: $6.05 8.28

Coolant Expansion Tank Cap - E36, E46, E34, E39, E38, X3, X5, Z3, Z4

Price: $6.64 9.09

Coolant Expansion Tank Cap, Aftermarket - E9X M3, E60 E63 F01 E70 E71

Price: $6.64 8.73

Threaded Cap for Coolant Level Sender Delete - E30 E36

Price: $7.47 7.86

Radiator Cap 1.4 Bar - E30 325e/325i & E34 525i M20 - 17111742232

Price: $7.49 27.29

Expansion Tank Cap - 17114379047

Price: $7.99 28.93

Charge Air Cooler Reservoir Cap - Many 2015+ Models

Price: $7.99

Cooling System Plug, Rein - F3X, E60, F10, G30, E63, F06/F12/F13, F02, X5/X6

Price: $7.99

Expansion Tank Cap, CRP - 2002, E21, E12, E28, Big Coupe, E24, E23 735i, E26 M1

Price: $10.99 21.89

Coolant Expansion Tank Cap, Aftermarket - E82, F22, E9X, F3X, F10, F13, G30, F01, F02, F25, F26, G01, G02, E70, F15, G05, E71, F16, G06

Price: $10.99 13.00

Expansion Tank Retaining Clip - 17111707777

Price: $10.99 12.92

Coolant Expansion Tank Cap, OEM - E36, E46, E39, E38, X3, X5, Z3, Z4

Price: $11.24 21.36

Expansion Tank Cap, Reutter - Many Vintage BMW Applications

Price: $11.99 20.15

Expansion Tank Cap, CRP - E30 325i, E34 525i M20

Price: $13.99 26.23

Charge Air Cooler Reservoir Cap, BMW - Many 2015+ Models

Price: $15.42 16.23

Coolant/Washer Level Sensor (installs in expansion tank) - Many BMW (see list)

Price: $15.99 28.84

Coolant Expansion Tank Cap, Rein - E9X M3, E60 E63 F01 E70 E71

Price: $17.99 24.70

Coolant Expansion Tank Cap, Rein - E82, F22, E9X, F3X, F10, F13, G30, F01, F02, F25, F26, G01, G02, E70, F15, G05, E71, F16, G06

Price: $17.99 23.44

Coolant Level Sensor With Round Pins - E30 E34 E24 E32 (1987-1995)

Price: $17.99 65.54

Coolant Expansion Tank Cap, BMW - E82, F22, E9X, F3X, F10, F13, G30, F01, F02, F25, F26, G01, G02, E70, F15, G05, E71, F16, G06

Price: $19.62 27.96

Cap for Coolant Expansion Tank, BMW - G42 G20 G22 G26 G29

Price: $21.59 23.98

Expansion Tank, Rein - E30 318i, E36 318i/318ti, E34 525i, Z3 1.9

Price: $21.99

Coolant Expansion Tank Cap, BMW - G26 i4 e40/M50

Price: $22.58 27.96

Expansion Tank Cap, Genuine BMW - E30 M3, E28 M5

Price: $23.67 24.92

Auto Transmission Cooler Thermostat, Rein - E46, E83 X3, E53 X5, E85/E86 Z4

Price: $24.90 101.55

Coolant Expansion Tank - E30 / E36 / Z3 4 cylinder, E34 525i - 17111712835

Price: $24.99 102.47

Expansion Tank - 17111712835 - E36 / Z3 4-Cylinder and E34 525i

Price: $27.30 36.30

BMW Expansion Tank - 34321112399 - E10

Price: $29.99 98.41

Expansion Tank - URO - 17111741167

Price: $31.34 37.65

Expansion Tank Threaded Cap, BMW - E30 325e/325i, E28 528e, E24 633CSi

Price: $31.83 33.51

Coolant Expansion Tank - E32 735i Sedan (1988-1994)

Price: $33.56 43.19

Expansion Tank Kit, Rein - E30 318i, E36 318i/318ti, E34 525i, Z3 1.9

Price: $3.28
4.43

Price: $3.79
5.19

Price: $4.74
7.69

Price: $6.05
8.28

Price: $6.64
9.09

Price: $6.64
8.73

Price: $7.47
7.86

Price: $7.49
27.29

Price: $7.99
28.93

Price: $10.99
21.89

Price: $10.99
13.00

Price: $10.99
12.92

Price: $11.24
21.36

Price: $11.99
20.15

Price: $13.99
26.23

Price: $15.42
16.23

Price: $15.99
28.84

Price: $17.99
24.70

Price: $17.99
23.44

Price: $17.99
65.54

Price: $19.62
27.96

Price: $21.59
23.98

Price: $22.58
27.96

Price: $23.67
24.92

Price: $24.90
101.55

Price: $24.99
102.47

Price: $27.30
36.30

Price: $29.99
98.41

Price: $31.34
37.65

Price: $31.83
33.51

Price: $33.56
43.19