Engine, major: Engine rebuild or replacement, cylinder head, head gasket, turbo or supercharger, timing chain or timing belt.
Engine, minor: Oil leaks, accessory belts and pulleys, engine mounts, engine knock or ping.
Engine, cooling: Radiator, cooling fan, antifreeze leaks, water pump, thermostat, overheating.
Transmission (and clutch), major: Transmission rebuild or replacement, torque converter, clutch replacement.
Transmission (and clutch), minor: Gear selector or linkage, leaks, transmission computer, transmission sensor or solenoid, clutch adjustment, rough shifting, slipping transmission.
Drive system: Driveshaft or axle, CV joint, differential, transfer case, 4WD/AWD components, driveline vibration, traction control, electronic stability control (ESC), electrical failure.
Fuel system: Check engine light, sensors (includes O2 or oxygen sensor), emission control devices (includes EGR), engine computer, fuel cap, fuel gauge/sender, fuel injection system, fuel pump, fuel leaks, stalling or hesitation.
Electrical: Alternator, starter, hybrid battery and related systems, regular battery, battery cables, engine harness, coil, ignition switch, electronic ignition, distributor or rotor failure, spark plugs and wires failure.
Climate system: Blower (fan) motor, A/C compressor, condenser, evaporator, heater system, automatic climate control, refrigerant leakage, electrical failure.
Suspension: Shocks or struts, ball joints, tie rods, wheel bearings, alignment, steering linkage (includes rack and pinion), power steering (pumps and hoses, leaks), wheel balance, springs or torsion bars, bushings, electronic or air suspension.
Brakes: Antilock system (ABS), parking brake, master cylinder, calipers, rotors, pulsation or vibration, squeaking, brake failure or wear.
Exhaust: Muffler, pipes, catalytic converter, exhaust manifold, leaks.
Paint/trim: Paint (fading, chalking, cracking, or peeling), loose interior and exterior trim or moldings, rust.
Body integrity: Squeaks, rattles, wind noises, loose or cracked seals and/or weather-stripping, air and water leaks.
Body hardware: Power or manual windows, locks and latches, tailgate, hatch or trunk, doors or sliding doors, mirrors, seat controls, safety belts, sunroof, convertible top.
Power equipment and accessories: Cruise control, clock, warning lights, body control module, keyless entry, wiper motor or washer, tire pressure monitor, interior or exterior lights, horn, gauges, 12V power plug, remote engine start, alarm or security system
Audio system (excluding aftermarket systems): Radio, speakers, antenna, CD or DVD player; GPS, iPod & MP3 interface; communication system (e.g. ONSTAR, Bluetooth), backup camera/sensors.
Key for reliability ratings
From "better to worse"