Car Problem Reports

BMW X3 Coolant Loss Due to Leak from Expansion Tank

BMW X3 Problem
22 Reports
Me Too

Model Years Affected: 2004, 2005, 2006, 2007, 2008

Average Mileage: 88,026 mi (64,000 mi - 120,000 mi)


An engine coolant leak may develop from the expansion tank resulting in engine overheating. When a cooling system component fails the entire cooling system should be inspected. It is not uncommon to find additional component have failed or are leaking.

Overheating can cause severe engine damage. If the engine begins to overheat it is recommended to stop at the first available location and have your vehicle towed to a repair shop.

  • Visitor, , 70,000 mi

    Took to the dealer. They replaced the water pump under warranty (thanks for the freebie). Not until I aquired a high pressure oil leak that I noticed oil and antifreeze mixed on the garage floor. I bought an expansion new expansion tank from BMW for $116.00 ($59.00 part on the internet) and fixed the thing myself in a couplr hours.

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  • Visitor, , 64,700 mi

    Coolant low intermittently goes on and off. Never stays on. Mechanic (not the dealer) found a hairline crack & says it has a small leak, not enough to reach the ground. Wants to charge me $700 to replace the tank. Haven't fixed it yet - I am researching optios.

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  • Visitor, , 102,713 mi

    My coolant light has just come on and when out after three days and diagnostic that couldn't detect anything. Now my service engine soon light is on.

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  • Visitor, , 86,000 mi

    Expansion tank blew out just as I parked the car. Loud bang, then coolant just ran out all over the place. Crack on side of expansion tank must be 5-6" long.

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  • Visitor, , 86,000 mi

    I had the extension tank replaced about 2 years ago, and the coolant is leaking again.

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  • Visitor,

    Expansion tank cracked

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  • Visitor, , 81,000 mi

    replace expansion tank and thermostat that connected to the tank.

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  • Visitor, , 120,000 mi

    losing antifreeze constantly

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  • Bonesr4us, , 68,755 mi

    Coolant light was going on and off brought in to dealer, was told the expansion tank was cracked. After examing the tank, BMW said the cylinder head was cracked and the oil was thick and tarry.

    Car was serviced at an authorize mechanic at 55K.
    Customer service has requested BMW enginner to inspect engine.

    I got the impression they may suspect my maintaince under warranty.

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