BMW M8 Competition (F92)

The S63B44T4 retains the hot-V layout that places twin turbochargers between the cylinder banks. The rubber sections of the turbo coolant lines are exposed to extreme heat and degrade over time, typically between 60,000 and 100,000 km. Symptoms include low coolant warnings, visible coolant residue in the engine valley, and potentially overheating if ignored. Coolant can drip onto the alternator and cause secondary electrical damage. BMW issued a service information bulletin for this issue on N63/S63 engines and fitted improved metal lines on later production cars. Dealer repair runs €2,500-3,500 due to extensive labor accessing the lines between the cylinder banks. Independent specialists can often replace just the degraded rubber portions using aftermarket repair kits for €1,500-2,000. Checking coolant level regularly is essential preventive maintenance.

Each turbocharger has an electronic wastegate actuator controlling boost pressure. These can develop open circuit faults or stick, triggering drivetrain malfunction warnings, reduced power, and limp mode. Bank 2 failures appear more common on the S63 family. BMW issued SIB 01 07 21 acknowledging this issue. A single OEM actuator costs approximately €500-600, with labor bringing the total to €1,000-1,500 per side. If both sides fail or internal turbo damage results from a stuck wastegate, costs can reach €3,000-3,500. BMW does not sell the actuator separately from the turbo assembly in all markets, which can inflate costs. Always use OEM replacement parts as aftermarket actuators have been reported to cause persistent fault codes.

The S63 engine's hot-V design exposes gaskets to elevated temperatures that accelerate rubber degradation. The valve cover gaskets and oil filter housing gasket are the most commonly reported leak points, often appearing between 60,000 and 100,000 km. Oil seeping onto exhaust manifolds produces a burning smell and visible smoke. On the V8, both valve covers need attention, and the integrated design means the entire valve cover assembly often needs replacement. At an independent M specialist, expect €800-1,200 for valve cover gaskets and €400-600 for the oil filter housing gasket. BMW dealers can charge €1,500-2,000 for the combined repair. Many specialists recommend replacing both gaskets together to save on overlapping labor.

The hot-V design exposes valve stem seals to elevated temperatures, causing the rubber to harden and lose its sealing ability over time. Symptoms include a visible puff of blue smoke from the exhaust on cold start and increasing oil consumption. BMW considers up to 1 litre per 1,500 km as within specification for M engines, though many owners find this excessive. The S63B44T4 received improved seal materials compared to earlier N63 variants, making this less common than on older models. Repair requires removing the valve covers and replacing all 32 seals. Specialist workshops charge approximately €3,000-4,000, while BMW dealers can quote €5,000-6,000. Upgraded aftermarket Viton seals are available and are more heat-resistant than the original specification. This issue is less prevalent on the latest S63B44T4 than on earlier S63 and N63 versions.

The S63B44T4 uses an electric water pump that BMW specialists recommend monitoring closely after 80,000 km. The pump's plastic impeller can crack or deform under prolonged thermal stress, and the motor bearings can seize. Symptoms include fluctuating coolant temperature warnings and a whining noise from the front of the engine. If the pump fails completely while driving, the engine can overheat within minutes, potentially warping the cylinder head. Many specialists recommend preventive replacement at around 80,000-100,000 km. Replacement costs €1,200-2,000 at a specialist including parts and labor. The S63 also has auxiliary turbo water pumps that can fail separately.

The S63 uses four VANOS solenoids that rely on clean oil flowing through them. Over time, oil deposits accumulate and impair solenoid function, typically beyond 100,000 km. Symptoms include rough idle, misfires, hesitation under acceleration, and check engine lights. More severe failure can trigger limp mode. Using high-quality engine oil and maintaining strict oil change intervals (every 10,000 km or less) helps extend solenoid life. Each solenoid costs approximately €100-150 for the part, but with four solenoids and 2-3 hours of labor, total repair runs €500-1,000 at a specialist and up to €1,500 at a dealer.

The BMW M8 Competition uses an integrated brake system where a single electronic module handles ABS, DSC, and brake boost functions. BMW issued multiple recalls (21V-062 for 2020-2021 models, 24V-104 for 2023-2024 models) for a weld connecting the rotor and shaft inside this module. If the weld fails, the ABS and stability control may not function correctly, and braking effort increases significantly. The vehicle switches to a safe mode with higher pedal resistance. BMW replaces affected modules under recall free of charge. Outside of recall coverage, the IBS module is an expensive proprietary component costing €2,000-4,000 for replacement. Verify recall status before purchase.