Coolant Expansion Tank

The Behr 17111719110 is a direct-fit coolant expansion tank designed to replace the original component in select BMW models. This tank is crucial for the cooling system as it accommodates the expansion and contraction of engine coolant as it heats up and cools down. Over time, the plastic construction of original expansion tanks can become brittle and prone to cracking due to age, heat cycles, and exposure to coolant chemicals. Symptoms of a failing expansion tank include coolant leaks, the tank becoming foggy or opaque making level checks difficult, and potential engine overheating due to reduced cooling system pressure. This Mahle Behr expansion tank does not include the level sensor or expansion tank cap. It is recommended to replace the expansion tank when installing a new radiator to ensure the continued performance and service life of your BMW's cooling system. The product comes with a 2-year / 24,000-mile warranty. Fitment includes various BMW 5 Series (530i, 535i, 540i) and 7 Series (735iL, 740i, 740iL, 750iL) models from approximately 1988 to 1995. Specific fitment includes: 1988-1992 BMW 735iL (Automatic RWD Sedan 3.5L L6 M30 Gas), 1988-1994 BMW 750iL (Automatic RWD Sedan 5.0L V12 M70 Gas), 1989-1993 BMW 535i (Automatic & Manual RWD Sedan 3.5L L6 M30 Gas), 1993-1994 BMW 740i (Automatic RWD Sedan 4.0L V8 M60 Gas), 1993-1994 BMW 740iL (Automatic RWD Sedan 4.0L V8 M60 Gas), 1994-1995 BMW 530i (Automatic & Manual RWD Sedan 3.0L V8 M60 Gas), and 1994-1995 BMW 540i (Automatic & Manual RWD Sedan 4.0L V8 M60 Gas). Some customer reviews mention that fitment may require minor modifications, such as shaving mounting holes or forcing the part onto studs.