The 2020 Morgan Plus Six uses BMW's proven B58 3.0L turbo inline-six and ZF 8-speed automatic, both highly reliable. Issues stem from Morgan's hand-built nature—fragile mounting points, electrical gremlins from exposed wiring, and cooling system vulnerabilities from tight engine bay packaging.
Transmission Mount Failure
Common · medium severityTypical onset: 15,000-40,000 mi
Symptoms: Clunking on takeoff or aggressive shifts, Excessive drivetrain movement visible under acceleration, Vibration at idle in gear
Fix: Morgan's transmission mounts are undersized for the B58's torque delivery. Replacement requires chassis access and sometimes exhaust removal due to tight clearances. 3-4 hours labor. Aftermarket poly mounts last longer but transmit more NVH.
Estimated cost: $800-1,400
Transmission Oil Cooler Line Leaks
Occasional · high severityTypical onset: 20,000-50,000 mi
Symptoms: Transmission fluid pooling under vehicle, Harsh or delayed shifts when hot, Transmission overheat warnings on spirited drives
Fix: Hard lines routed near exhaust develop stress cracks from heat cycling. Leak depletes fluid quickly—can cook the ZF 8HP if driven low. Requires custom line fabrication or OEM replacement. 4-5 hours including fluid refill and system bleed.
Estimated cost: $1,200-2,000
LED Headlight Module Failures
Common · low severitySymptoms: Flickering low beams or DRL, One side dims or goes dark intermittently, Error messages for lighting malfunction
Fix: Morgan uses aftermarket LED modules that don't handle vibration and weather exposure well. Water intrusion through seals is typical. Entire headlight assembly replacement usually required—modules aren't serviceable separately. 1.5-2 hours per side.
Estimated cost: $1,500-2,800
Engine Bay Fuse Box Corrosion
Occasional · medium severitySymptoms: Random electrical faults—fuel pump, cooling fans, injectors, No-start conditions after rain or washing, Multiple unrelated warning lights
Fix: Fuse box is exposed to elements in Morgan's open engine bay design. Terminals corrode, causing intermittent high-resistance faults. Clean terminals and apply dielectric grease as preventive; severe cases need box replacement. Diagnosis 1-2 hours, repair 2-3 hours.
Estimated cost: $400-1,200
Cylinder Head Cooling System Stress
Rare · high severityTypical onset: 40,000-70,000 mi
Symptoms: Coolant loss with no visible leaks, White smoke on cold start, Overheating under load despite new thermostat/water pump
Fix: B58 head gasket failures are uncommon but catastrophic. Tight Morgan engine bay causes localized hot spots. Head removal, resurface, new gasket, and ARP studs recommended. 18-22 hours labor due to chassis access limitations. Some shops pull entire engine to work efficiently.
Estimated cost: $5,500-8,500
Fuel Filter Clogging (Ethanol Sensitivity)
Occasional · medium severityTypical onset: 30,000-60,000 mi
Symptoms: Hesitation or stumble under wide-open throttle, Limp mode above 4,500 RPM, Lean codes (P0171/P0174)
Fix: BMW fuel systems are ethanol-sensitive; Morgan's exposed tank vents accelerate moisture contamination. Replace filter every 30k miles versus BMW's 60k spec. Filter is chassis-mounted, requires fuel system depressurization. 1.5 hours labor.
Estimated cost: $300-500
Buy it for the driving experience and BMW mechanicals, but budget $1,500/year for Morgan-specific quirks—only worth it if you have garage space and accept hand-built compromises.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.