Our coolant overflow bottles are some of the highest quality replacements on the market!


  • Direct replacement for originals that are cracked or broken
  • Strengthened and redesigned in the vulnerable areas of failure
  • Plastic construction
  • Commonly called Expansion Tank by BMW
  • Fits E31, E38, & E39 body chassis as listed
  • Does not include cap or coolant lever sensor
    • Buyer will need to reuse original cap & Sensor

Now you can buy a high quality coolant reservoir that is built to strict quality control standards. REPLACE your broken or cracked one now with this great fitting Radiator Overflow Bottle.

Lifetime Warranty

This item is backed by a Limited Lifetime Warranty. In the event this item should fail due to manufacturing defects during intended use, we will exchange the part free of charge (excludes shipping charges) for the original purchaser. Please keep your invoice for proof of this warranty.

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Vehicle Fit

  • 1997-2003 BMW 540i Radiator Overflow Bottle
  • 1999-2000 BMW 540iT Radiator Overflow Bottle
  • 1995 BMW 740i Radiator Overflow Bottle
  • 1997-2001 BMW 740i Radiator Overflow Bottle
  • 1995-2001 BMW 740iL Radiator Overflow Bottle
  • 1995-2001 BMW 750iL Radiator Overflow Bottle
  • 1994-1997 BMW 840Ci Radiator Overflow Bottle
  • 1994-1995 BMW 850CSi Radiator Overflow Bottle
  • 1993-1997 BMW 850Ci Radiator Overflow Bottle
  • 1991-1992 BMW 850i Radiator Overflow Bottle
Only 3 left in stock
Part #: 1AROB00027

Ships Same Day for orders placed by 4 P.M. ET

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Customer Feedback

"Thanks for the fast reliable service. Great price, and the headlights were as good as oem or better!!! Keep up the good work..."
- Dwuan M.
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