2018 BMW 5-Series Reliability Score & Common Problems

Owners report several issues with the 2018 BMW 5-Series, particularly related to coolant leaks and electronic malfunctions. Complaints frequently mention coolant leaks from plastic components such as the oil housing unit and coolant vent lines, often occurring around 60,000 to 70,000 miles. Additionally, multiple owners describe problems with safety and convenience features, including ineffective rear cross-traffic alert systems and steering wheel vibration alerts, as well as a malfunctioning Telematics Control Unit. One complaint involves a crash due to unintended acceleration, resulting in two injuries, highlighting a potential safety risk. Buyers should be aware of these recurring issues and consider them when evaluating the vehicle's reliability and safety.

Owners of the 2018 BMW 5-Series frequently report issues with the passenger restraint system and seat belt warnings. A common symptom described is the "passenger restraint system malfunction" message appearing intermittently, sometimes linked to weather conditions like dampness. Additionally, several complaints highlight the passenger seat belt not recognizing occupancy, leading to the airbag being turned off, with one report involving a crash and injury due to the seat belt not locking correctly. Some owners mention costly repairs, with estimates around $2,000 to $2,800 for sensor mat replacements. These issues are reported across various mileage ranges and are often recurrent, even after attempted repairs.

Owners of the 2018 BMW 5-Series report several power train issues, with some incidents resulting in crashes and injuries. A common problem involves the vehicle shutting off unexpectedly, often accompanied by warning messages such as "transmission not in park" or "drivetrain malfunction," typically linked to fuel pump failures. Another issue involves sudden, uncontrollable acceleration from a complete stop, leading to loss of control and accidents, as described in one report where the car accelerated into a ditch, causing a fracture to the driver. Additionally, some owners mention coolant leaks leading to engine jerking and potential head gasket damage. These issues can occur at various mileages, with one owner noting problems beginning in November 2022. Safety implications include crashes and injuries, highlighting potential risks for used car buyers considering this model.

Owners of the 2018 BMW 5-Series report issues primarily related to coolant leaks and engine warning lights. Complaints frequently mention coolant leaks leading to engine damage, with symptoms including illuminated check engine lights and coolant level warnings. These issues often occur around 64,000 to 105,000 miles. Some owners describe repeated repairs, such as coolant hose replacements, that fail to resolve the problem. No safety implications like crashes or loss of control are reported, but potential buyers should be aware of these recurring coolant system issues.

Owners of the 2018 BMW 5-Series report issues with vehicle speed control, particularly involving the cruise control system and sudden unintended acceleration. One complaint describes a cruise control rocker switch that gets stuck, causing the vehicle to accelerate uncontrollably beyond the intended speed. Another complaint involves sudden unintended acceleration while parking, leading to a crash with a parked car. These incidents suggest potential safety risks, including the possibility of crashes due to loss of speed control. No specific mileage patterns are noted, but one owner reports ongoing issues since November 2018. Buyers should be aware of these potential speed control problems when considering this model.

Owners of the 2018 BMW 5-Series report issues with the steering system, primarily involving sudden loss of power steering assistance. Complaints frequently mention warning lights for collision, steering, and pedestrian systems illuminating, followed by the steering becoming difficult to maneuver, effectively reverting to manual steering. These issues are reported to occur without prior warning and have been noted at various mileages, including one instance at 31,000 miles. A significant safety implication is highlighted by instances where the steering wheel locks up, nearly causing accidents. Prospective buyers should be aware of these potential steering issues and their associated safety risks.

Owners of the 2018 BMW 5-Series report issues with the service brakes, with specific complaints about brake pad wear and sudden unintended acceleration. One owner describes a situation where the rear brake pads wore down to the metal without triggering a brake wear warning light, occurring around 40,000 miles. Another owner reports a crash incident where the vehicle unexpectedly accelerated from a stop, despite the brake pedal being fully depressed, leading to a collision with another stopped vehicle. These complaints highlight potential safety implications, particularly concerning brake system warnings and sudden acceleration incidents.