— BMW B46, B48 and B58 engines contain oil filter housings that leak coolant and forces owners to spend thousands of dollars for repairs and replacements.
That view is held by three customers who filed a BMW oil filter housing lawsuit which covers these vehicles equipped with B46, B48 or B58 engines.
- 2014-2021 BMW 1 Series
- 2014-2021 BMW 2 Series
- 2014-2021 BMW 3 Series
- 2014-2021 BMW 4 Series
- 2014-2021 BMW 5 Series
- 2014-2021 BMW X1, X2, X3, X4
- 2014-2021 MINI Cooper
- 2014-2021 MINI Cooper Clubman
- 2014-2021 MINI Cooper Countryman
The BMW class action says the oil filter housing should last at least 150,000 miles. But owners complain of paying up to $4,000 for oil filter housing replacements after 60,000 miles. BMW customers say a typical oil filter housing replacement is always $1,500 to $3,500, based on the vehicle.
The BMW lawsuit says the B46, B48 and B58 engine oil filter housings contain cartridge-type oil filter components and the oil coolers. This oil filter housing attaches by bolt fasteners to the side of the engine block.
But the class action alleges the B46, B48 and B58 engines experience premature oil filter housing and gasket failures because the "polycarbonate housing and sealing gaskets become embrittled due to repeated heating and cooling cycles."
"More specifically, the oil filter housing internal wall structures separating the oil and coolant passages fail and/or warp and/or gaskets sealing the various oil and water passages fail. This occurrence causes the loss of engine coolant that either leaks into the oil sump or drains externally that can result in engine overheating and/or failure." — BMW oil filter housing class action lawsuit
The plaintiffs assert BMW phased out cast aluminum engine oil filter housings and switched to "inferior polycarbonate housings" around 2011. But since 2015 the automaker has reportedly concealed all the problems related to the polycarbonate oil filter housings in B46, B48 and B58 engines.
Illinois plaintiff Aaron Eiger says he purchased a used MINI Countryman S in December 2020, but the engine oil filter housing leaked coolant in July 2025 when the MINI had about 62,400 miles on it. The oil filter housing replacement cost nearly $1,700.
North Carolina plaintiff Kendra Cherry purchased a used 2019 BMW X3 in May 2022. But in November 2024 the vehicle required replacement of the oil filter housing what was leaking coolant. The BMW engine had 79,312 miles on it.
California plaintiff Kelly Haley Fucillo purchased a used 2018 BMW 430i in August 2025, but in January 2026 the leaking engine oil filter housing required replacement. The BMW engine had 68,342 miles on it and the oil filter housing cost the plaintiff about $4,000.
The lawsuit references actions by BMW due to coolant leaks from the oil filter housings.
BMW SIB 11 10 25 was issued to dealers because the oil filter housing seal could put too much pressure on the bushing/insert in the oil filter housing. The pressure could cause the insert to deform and create an external coolant leak.
(The above photo shows the crack in the oil filter housing coolant bushing/insert.)
The class action also asserts the oil filter housing coolant leaks decrease the value of a BMW vehicle.
The BMW oil filter housing coolant leak lawsuit was filed in the U.S. District Court for the District of New Jersey: Eiger, et al., v. BMW of North America, LLC.
The plaintiffs are represented by Kantrowitz, Goldhamer & Graifman, P.C., and Thomas P. Sobran P.C.
