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Packaged by Turner BMW Coolant Expansion Tanks

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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Packaged by Turner - Corporate Logo
T#:338020
Part#: 17117573781
In Stock at Vendor
Sale - Save 2% $ 140.99

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

Starting at $ 137.98 USD
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Sale - Save 2%
$ 140.99

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

Starting at $ 137.98 USD
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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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Packaged by Turner - Corporate Logo
T#:27605427
Part#: 17138677649TKT
In Stock at Vendor
Sale - Save 4% $ 208.99

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

$ 200.20 USD
Free Shipping on orders $49 and up
Sale - Save 4%
$ 208.99

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

$ 200.20 USD
Free Shipping on orders $49 and up
Genuine BMW expansion tanks have a bad habit of failing after a few years. This has primarily been caused by the plastic construction of the expansion tanks. After enough heat cycles, the plastic becomes brittle and can crack, causing coolant to leak out and air to enter the coolant system. If a failing expansion tank is not addressed soon enough, the coolant loss can lead to an overheating engine. This kit includes two brand new high quality expansion tanks and caps
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Packaged by Turner - Corporate Logo
T#:338018
Part#: 17111723520
In Stock at Vendor
$ 97.99

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

Starting at $ 77.22 USD
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Starting at $ 77.22 USD
Free Shipping
This high quality BEHR brand expansion tank is used on M50, M52, S50 and S52 engines, and is a common failure item on all E36 3 series with 6 cylinder engines (325/328/323 and M3) 1992-1999, Z3 with 2.8 liter, MZ3 Roadster/Coupe (S52), and E39 528i from 1997-1998. BEHR was the original equipment supplier to BMW, so you know the BEHR made expansion tank will be the highest quality available. Be leary of competitors selling this part for less -- is it a BEHR? Probably not. We only carry the BEHR brand expansion tank as it is the only one we use in our own BMWs.

If you are overhauling your coolant system, now is the time to consider preventative replacing this expansion tank. These are known to go bad, causing a leak which can leave you stranded. 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.

Need a new coolant level sensor too? If your coolant level sender is bad, your on board computer will constantly display a "low coolant" message (unless your coolant is actually low...). If you're replacing your expansion tank, now is a great time to replace this failure prone sensor. If you want a new coolant level sensor, simply choose from the option below. Because there are different sensors for different year/model BMWs, please be as specific as possible when you give us your car info during checkout (model, year, production date). Thanks!


This item fits the following BMWs:
1992-1998 E36 BMW 323ic 325i 325is 325ic 328i 328is 328ic M3
1997-1998 E39 BMW 528i
1997-1998 Z3 BMW Z3 2.8
1998-2000 Z3 BMW M Roadster M Coupe (S52)
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Packaged by Turner - Corporate Logo
T#:15677514
Part#: 11281706545-KT
In Stock
Sale - Save 4% $ 474.99

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

$ 457.71 USD
Free Shipping on orders $49 and up
Sale - Save 4%
$ 474.99

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

$ 457.71 USD
Free Shipping on orders $49 and up
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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Packaged by Turner - Corporate Logo
T#:15677493
Part#: 11517527910-KT
In Stock
Sale - Save 5% $ 337.99

This product was last offered at the strikethrough price on
02-27-2026

$ 321.90 USD
Free Shipping on orders $49 and up
Sale - Save 5%
$ 337.99

This product was last offered at the strikethrough price on
02-27-2026

$ 321.90 USD
Free Shipping on orders $49 and up
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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Packaged by Turner - Corporate Logo
T#:15744017
Part#: N524ECSTNKKT-KT
In Stock
Sale - Save 40% $ 166.99

This product was last offered at the strikethrough price on
04-03-2026

$ 100.95 USD
Free Shipping on orders $49 and up
Sale - Save 40%
$ 166.99

This product was last offered at the strikethrough price on
04-03-2026

$ 100.95 USD
Free Shipping on orders $49 and up
The coolant expansion tank in your vehicle gives additional fluid a place to go after expansion and contraction from temperature change. Because it is subjected to such drastic changes on a regular basis, it can often crack or break. You want to keep all the coolant in your vehicle in the cooling system. If your tank has experienced damage such as cracking, nipples breaking off, or mounting point damage, you will need to replace it. The kit includes: Expansion tank with level sensor URO expansion tank cap Genuine BMW expansion tank grommet Genuine BMW mounting bolts
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Packaged by Turner - Corporate Logo
T#:584232
Part#: 17112283345KT
In Stock
$ 249.99 USD
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$ 249.99 USD
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The expansion tank in your BMW is a vital component of the cooling system, and because of the constant abuse from heat and temperature changes, it often fails. This kit contains all of the basic items needed for a tank replacement.
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Packaged by Turner - Corporate Logo
T#:15710821
Part#: 17137607482-KT
In Stock
Sale - Save 6% $ 781.99

This product was last offered at the strikethrough price on
04-06-2026

$ 734.48 USD
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Sale - Save 6%
$ 781.99

This product was last offered at the strikethrough price on
04-06-2026

$ 734.48 USD
Free Shipping on orders $49 and up
As your mileage increases, so does wear and tear on your engine's cooling components. Cooling system components live a rough life, going through extreme temperature changes and being exposed to the elements. A cooling system failure can, and probably will leave you stranded. Included in this kit Water pump with new bolts Thermostat & housing Expansion tank with level sensor Expansion tank cap 1 Gallon of OEM Coolant Waterpump & thermostat hoses Upper and lower radiator hoses Accessory belt
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Packaged by Turner - Corporate Logo
T#:15744066
Part#: 11287837898-KT
Ships on Dec 7, 2026
Sale - Save 8% $ 808.99

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

$ 746.03 USD
Free Shipping on orders $49 and up
Sale - Save 8%
$ 808.99

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

$ 746.03 USD
Free Shipping on orders $49 and up
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 - Corporate Logo
T#:42099868
Part#: 11537558523TKT
Back Ordered
Sale - Save 19% $ 829.99

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

$ 671.10 USD
Free Shipping on orders $49 and up
Sale - Save 19%
$ 829.99

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

$ 671.10 USD
Free Shipping on orders $49 and up
Keep your BMW running at the proper temperature and avoid costly engine repairs with the Cooling System Refresh Kit, the complete maintenance solution trusted by enthusiasts and professionals alike.
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Packaged by Turner - Corporate Logo
T#:15677500
Part#: 82141467704-KT
Back Ordered
Sale - Save 19% $ 832.99

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

$ 672.89 USD
Free Shipping on orders $49 and up
Sale - Save 19%
$ 832.99

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

$ 672.89 USD
Free Shipping on orders $49 and up
As your mileage increases, so does wear and tear on your engine's cooling components. Cooling system components live a rough life, going through extreme temperature changes and being exposed to the elements. A cooling system failure can, and probably will leave you stranded. For automatic transmission (or DCT) vehicles only This kit includes: Thermostat with mounting hardware 1 gallon of BMW coolant Water pump with mounting hardware Primary cooling system hoses and radiator hose gasket, and bleeder screw Expansion tank with cap Accessory belt
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