OEM parts categories for 2020 Audi A4: A/C & Heating (A/C & Heater Control Units, A/C Condenser, Compressor & Lines, A/C Evaporator Components, Air Conditioner, Automatic Temperature Controls, Blower Motor & Fan, Heater Components, Heater Core & Control Valve, HVAC Case, Switches & Sensors) | Air & Fuel Delivery (Air Intake, Cruise Control, Fuel Injection, Fuel Supply, Fuel System Components, Intake Manifold, Intercooler, Throttle Body, Turbocharger) | Belts & Cooling (Belts & Pulleys, Cooling System, Radiator, Water Pump, Cooling Fan, Hoses & Lines, Intercooler, Radiator & Components, Trans Oil Cooler, Water Pump) | Body & Hardware (Aperture Panel, Uniside, Bumper & Components - Front, Bumper & Components - Rear, Center Pillar & Rocker, Cluster & Switches, Instrument Panel, Console, Cowl, Dash Panel Components, Door & Components, Ducts, Electrical Components - Front Bumper, Electrical Components - Rear Bumper, Fender & Components, Floor & Rails, Front Door, Front Door Glass & Hardware, Front Seat Components, Glass & Hardware - Back Glass, Glass & Hardware - Quarter Panel, Glove Box, Grille & Components, Hinge Pillar, Hood & Components, Information Labels, Inner Structure - Quarter Panel, Jack & Components, Lock & Hardware, Outside Mirrors, Quarter Panel & Components, Radiator Support, Rear Body, Rear Door, Rear Floor & Rails, Rear Seat Components, Rear Spoiler, Roof & Components, Seat Belt, Sound System, Splash Shields, Structural Components & Rails, Sunroof, Trunk, Trunk Lid & Components, Under Cover & Splash Shields, Windshield Glass, Reveal Moldings, Wiper & Washer Components) | Brakes (Anti-Lock Brakes, Brake Components, Front Brakes, Hydraulic System, Parking Brake, Rear Brakes) | Charging & Starting (Alternator, Battery, Starter) | Driveline & Axles (Axle Shafts & Joints, Drive Axles) | Electrical (ABS Components, Air Bag Components, Alarm System, Antenna & Radio, Anti-Theft Components, Communication System Components, Electrical Components, Front Door, Front Seat Belts, Fuel Door, Fuse & Relay, Heated Seats, Horn, Ignition Lock, Ignition System, Instruments & Gauges, Keyless Entry Components, Lane Departure Warning, Lumbar Control Seats, Mirrors, Navigation System, Parking Aid, Power Seats, Powertrain Control, Rear Door, Rear Seat Belts, Senders, Starter, Sunroof, Switches, Trunk, Washer Components, Wipers, Wiring Harness) | Emission Control & Exhaust (Emission Components, Exhaust Components, Exhaust Manifold, Heat Shields) | Engine (Engine & Trans Mounting, Engine Appearance Cover, Engine Parts, Mounts, Cylinder Head & Valves, Camshaft & Timing, Oil Pan, Oil Pump, Balance Shafts, Crankshaft & Bearings, Pistons, Rings & Bearings, Transaxle Parts, Turbocharger & Components, Valve & Timing Covers) | Headlights & Lighting (Backup Lamps, Headlamp Components, Headlamps, Headlamp Washers/Wipers, High Mount Lamps, License Lamps, Tail Lamps) | Interior & Exterior Trim (Exterior Trim - Fender, Exterior Trim - Front Door, Exterior Trim - Pillars, Exterior Trim - Quarter Panel, Exterior Trim - Rear Door, Exterior Trim - Trunk, Interior Trim - Front Door, Interior Trim - Pillars, Interior Trim - Quarter Panels, Interior Trim - Rear Body, Interior Trim - Rear Door, Interior Trim - Roof, Interior Trim - Trunk) | Maintenance & Lubrication (Automatic Transmission, Belts & Pulleys, Filters) | Steering (Shroud, Switches & Levers, Steering Column & Wheel, Steering Gear & Linkage) | Suspension (Axle & Differential - Rear, Drive Axles - Front, Drive Axles - Rear, Drive Shaft - Rear, Front Suspension Components, Lower Control Arm, Stabilizer Bar, Rear Suspension Components, Lower Control Arm, Upper Control Arm, Stabilizer Bar, Shocks & Components - Rear, Stabilizer Bar & Components - Front, Struts & Components - Front, Suspension Mounting - Front, Suspension Mounting - Rear, Wheels) | Transmission (Automatic Transmission, Gear Shift Control - AT, Valve Body)