Subject: Safety Defect Report – B58TU Oil Pump Failure Causing Sudden Vehicle Disablement I am submitting a safety defect report regarding BMW vehicles equipped with the B58 Technical Update engine, primarily model years 2019 to 2021 including 340i, 440i, 540i, X3 M40i, and Toyota Supra models using this engine variant. These vehicles utilize a variable displacement oil pump that contains an internal thermoplastic pressure-regulating component. Field reports indicate this internal component fractures, resulting in sudden loss or instability of engine oil pressure. Failures frequently occur during cold start operation in low ambient temperatures. In many cases, drivers receive limited or no actionable warning before drivetrain malfunction messages appear or the vehicle becomes disabled. Reported symptoms include: • Inability to measure engine oil level electronically • Oil pressure irregularities • Sudden drivetrain malfunction warnings • Engine shutdown or severe internal damage due to oil starvation Loss of lubrication can cause sudden vehicle disablement in active traffic or in freezing conditions. This creates a safety hazard due to immobilization and exposure risk. Repair costs for oil pump replacement commonly exceed $6,000 to $8,000, not including secondary engine damage. Owners cannot verify whether their vehicles contain the original thermoplastic pump or a revised metal-internal version, as parts catalog data now defaults to the updated component regardless of vehicle production configuration. Because this defect can lead to sudden loss of propulsion without adequate warning, I request formal investigation into this condition as a safety-related defect.
- NHTSA ID
- 11721144
- Incident
- Feb 28, 2026
Took 2017 BMW 440i in for annual state inspection and maintenance. During inspection, service tech noticed that the plastic clip that holds the emergency brake lines in place had failed and needed to be replaced to prevent damage to the emergency brake cables. Service tech replaced the plastic clip with a metal bolt. My service advisor stated that a plastic clip should have never replaced a metal bolt that is used to protect the emergency brake cables. Have owned BMW’s since 1990 and numerous vehicles since 1968 when I obtained my driver’s license. Paid $804.47 to replace a plastic clip that would have cost nothing if a metal bolt had been used to start with. If the brake lines get damaged because the clip fails, you have no brakes on the vehicle. Spoke with BMW customer service and they said since the clip failed after the warranty period they would not reimburse the repair even though replacing a metal bolt on an emergency brake cable would prevent failure. A car that is garaged and only has 13,263 miles on it should not experience this type of failure. How many vehicles are on the road with failing plastic clips that allow brake lines to fail because a manufacturer decided to save money by taking a proven metal bolt and replacing it with plastic that fails with age.
- NHTSA ID
- 11710856
- Incident
- Nov 21, 2025
Interior & seats
Filed May 10, 2024
The Passenger Restraint System was failing and is now constantly showing a Passenger Restraint System alert. It can not tell whether a passenger is in the seat or not. A local BMW specialist says it is a common issue with the passenger occupancy mat.
- NHTSA ID
- 11588043
- Incident
- Dec 22, 2023
BMW 4 series has a TSB for leaking coolant this one is not listed but same part and part number is defective and leaking
- NHTSA ID
- 11510556
- Incident
- Jan 1, 2023
Body & structure
Filed Sep 27, 2020
CONVERTIBLE TOP LEAKS REAR PASSENGER SIDE AND DRIVER SIDE WHEN HEAVY RAIN AND WASHING MY VEHICLE WITH MY HOSE SPRAYER. HAVE REPORTED IT OVER AND OVER THEY'RE SAYING YOU CANNOT USE A HIGH-PRESSURE HOSE ON THE VEHICLE IT'S NOT HIGH PRESSURE. IT LEAKED WHEN TRAVELING DOWN THE HIGHWAY WHEN IT WAS RAINING AND SITTING STEEL IN MY DRIVEWAY AS I WASHED IT IT ALSO LEAKS AFTER THEY RECENTLY FIXED THE VEHICLE WHEN THEY WASHED IT AND THEY'RE SAYING OH WE USE THE HIGH PRESSURE HOSE AND THEY TOLD ME YOU'RE NOT SUPPOSED TO USE A HIGH-PRESSURE HOSE TO WASH THE CAR.THIS HAS OCCURRED OVER A PERIOD OF YEARS
- NHTSA ID
- 11361425
- Incident
- Jun 20, 2020
Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.