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Packaged by Turner BMW Coolant Expansion Tanks for BMW 3 Series E46 (1999-2005)

On certain models, namely E36, E46, and E90, the factory BMW expansion tank is prone to either breaking at connection points or blowing apart altogether. If you're starting to feel like your expansion tank is on borrowed time, it's probably time to replace with either a direct OE replacement, or strengthen your cooling setup with an aluminum expansion tank - we offer numerous performance upgrades for your expansion tank. Especially if you're someone who likes to track your BMW, we recommend upgrading your expansion tank to avoid ruining your track day.

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Coolant Expansion Tank - E46 (non-M), X3, X5 3.0

10X Entries Into Our F80 M3 Sweepstakes

T#:338020

Part#: 17117573781

In Stock at Vendor

Sale - Save 9% $ 140.99

This product was last offered at the strikethrough price on
04-01-2026

Starting at $ 128.98 USD

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Sale - Save 9%

$ 140.99

This product was last offered at the strikethrough price on
04-01-2026

Starting at $ 128.98 USD

Add to Wish List

This coolant reservoir is for the non-M E46 3-series models from 1999-2006 (M3 takes a different expansion tank). We have found that the expansion tanks should be replaced based on age as well as condition. Expansion tanks seem to have a lifespan of less than six years before they show signs of fatigue and wear. Pre-emptively replacing the expansion tank as part of an overall maintenance plan can prevent you from getting stranded from a sudden failure later on. This is the most recent expansion tank design from Hella-Behr, the OEM supplier to BMW. It replaces the original BMW part number 17137787039.

Other items to consider replacing at the same time are the radiator cap, coolant level sensor, lower radiator hose, coolant temp sensor in the lower hose, and the hose clamps. If your car has an automatic transmission you should also replace the oil cooler thermostat in the radiator frame, which is a common source for leaks.

This coolant expansion tank fits:

1999-2006 E46 3 series - 323i, 323Ci, 325i, 325Ci, 325xi, 328i, 328Ci, 330i, 330Ci & 330xi (**no M)
2004-2008 X3 SAV - X3 2.5, X3 3.0, X3 3.0si
2000-2005 X5 SAV - X5 3.0

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ECS Cooling System Refresh Kit - Level 1

10X Entries Into Our F80 M3 Sweepstakes

T#:15677493

Part#: 11517527910-KT

In Stock

Sale - Save 4% $ 336.99

This product was last offered at the strikethrough price on
05-03-2026

$ 324.43 USD

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Qty

Sale - Save 4%

$ 336.99

This product was last offered at the strikethrough price on
05-03-2026

$ 324.43 USD

Add to Wish List

Stop the problems before they arise. If you vehicle has 80,000 miles or more, replace all of these components to ensure that your vehicle stays healthy. To keep everything in top order, continue to replace these components at 80,000 mile intervals. Water pump failure, cracked plastic housings, and expansion tank leaks will not be a concern once all these problem parts are replaced. This kit was put together by Turner including the basic parts that need replaced. Water pump with metal impeller Fan switch Thermostat and thermostat housing Sealing gaskets Expansion tank with level sensor, clamp and cap 1 Gallon Coolant Upper & lower radiator hoses

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ECS Cooling System Refresh Kit - Level 2

10X Entries Into Our F80 M3 Sweepstakes

T#:15677514

Part#: 11281706545-KT

In Stock

Sale - Save 3% $ 474.99

This product was last offered at the strikethrough price on
05-03-2026

$ 460.24 USD

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Qty

Sale - Save 3%

$ 474.99

This product was last offered at the strikethrough price on
05-03-2026

$ 460.24 USD

Add to Wish List

Stop the problems before they arise. If your BMW has 80,000 miles or more, replace all of these components to ensure that your vehicle stays healthy. Avoid water pump failure, cracked thermostat housings, and expansion tank leaks, which all lead to overheating and subsequent damage. This kit was put together by Turner for a complete cooling system service. GEBA water pump with metal impeller ECS aluminum water pump pulley Fan switch Thermostat and thermostat housing Sealing gaskets Expansion tank with level sensor, clamp and cap 1 Gallon Coolant Upper & lower radiator hoses Accessory drive belts Radiator drain plug

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Cooling System Refresh Kit - Level 2

10X Entries Into Our F80 M3 Sweepstakes

T#:15744066

Part#: 11287837898-KT

Ships on Dec 7, 2026

Sale - Save 26% $ 808.99

This product was last offered at the strikethrough price on
07-15-2026

$ 596.54 USD

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Qty

Sale - Save 26%

$ 808.99

This product was last offered at the strikethrough price on
07-15-2026

$ 596.54 USD

Add to Wish List

BMW has been designing notoriously failure-prone cooling systems since the late 1980s. The coolant capacity in most BMW engines is not sufficient to accommodate any driving or overheating near red zone temperatures. After the gauge reaches this critical area, it is common for thousands of dollars in damage to occur. Stop the problems before they arise. If your vehicle has 80,000 miles or more, replace all of these components to ensure that your vehicle stays healthy. To keep everything in top order, continue to replace these components at 80,000 mile intervals. Water pump failure, cracked housings, and expansion tank leaks will not be a concern once all these problem parts are replaced. Saleri water pump with metal impeller ECS aluminum water pump pulley Fan switch Vaico Q+ thermostat - made in Germany! Sealing gaskets Expansion tank with level sensor, clamp and cap 1 Gallon Coolant Upper & lower radiator hoses Accessory drive belts Radiator drain plug

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Packaged by Turner BMW Coolant Expansion Tanks for BMW 3 Series E46 (1999-2005)

Coolant Expansion Tank - E46 (non-M), X3, X5 3.0

ECS Cooling System Refresh Kit - Level 1

ECS Cooling System Refresh Kit - Level 2

Cooling System Refresh Kit - Level 2

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