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2021 Audi A4 Quattro

Factory specifications, fluid capacities, torque values, EPA fuel economy and the federal safety record for the 2021 A4 Quattro.

Transmission Automatic (AM-S7)

The 2021 Audi A4 Quattro is a compact executive sedan featuring all-wheel drive and a 7-speed automated manual transmission (AM-S7), achieving EPA fuel economy ratings of 25 mpg city, 34 mpg highway, and 28 mpg combined, figures that position it competitively within its segment for efficiency without sacrificing the brand's signature Quattro traction capability; this model year carries four safety recalls, with electrical system issues representing the most frequent owner complaint among the 11 total reported, indicating that while the A4 remains a well-established model within Audi's lineup, prospective buyers should note these specific areas of concern when evaluating long-term ownership costs and reliability expectations.

Model year2025202420232022202120201996

Quick specs

Fluid capacities, tune-up values and fuel economy at a glance.

Lug nut torque89 ft-lbsOEM · verified
EPA fuel economy25/34/28 mpgEPA · verified

Fitment & sizes

Replacement part sizes and factory part numbers — battery, bulbs, filters and belts.

From the factory this vehicle uses a BCI 49 · 92AH CCA battery, OE oil filter 06L115562B. Each part links to every other vehicle that shares it, so a part you already stock may fit more of your fleet than you'd expect.

Battery groupBCI 49 · 92AH CCAOEM · verified
Tire size201 HP: 225/50R17 94H; 261 HP: 245/40R18/XL 97HOEM · verified
Wheel / rim201 HP: 7.5; All Others: 8 inOEM · verified

OE service part numbers OEM · verified

Engine oil filter06L115562B
Engine air filter8W0133843C
Spark plug06Q905601A
Battery8W0915089A
Front wiper blades8W1998002
Cabin air filter4M0819439C

Full specifications

Engine, drivetrain, dimensions and economy.

Engine & drivetrain NHTSA vPIC

TransmissionAutomatic (AM-S7)

Dimensions & weight NHTSA vPIC

Overall length187.4 in
Overall width72.8 in
Overall height56.3 in
Wheelbase111 in
Curb weight3633 lb
Track (front / rear)61.8 / 61 in
Weight distribution (front / rear)56/44

Ratings & economy EPA / vPIC

EPA city / highway / combined25 / 34 / 28 mpg
DrivetrainAll-Wheel Drive
Passenger volume92 cu ft
Cargo volume12 cu ft
Recommended fuelPremium Gasoline

Service quick specs OEM factory data

Capacities, torques and tune-up values from the factory service manual.

This engine DOT 4 brake fluid. Torque lug nuts to 89 ft-lbs. The firing order is 1-3-4-2.

Lubricants & capacities

Brake FluidDOT 4
Clutch FluidDOT 4

Engine torques

Cylinder Head InstructionsOnly use new bolts.

Chassis torques

Lug Nuts89 ft-lbs

Ignition

Cylinder Firing Order1-3-4-2

Battery & A/C

RefrigerantR1234yf
Refrigerant Capacity1.12-1.18 lbs
Oil Capacity3.50-4.10 oz
Standard BCI Group Number49
Standard BCI Cranking Performance92AH cca
Optional BCI Group Number95R
Optional BCI Cranking Performance110AH cca

Service checks

Fuel Pump Pressure Minimum87.0 psi
Fuel Pump Pressure Maximum116.0 psi
Residual Pressure43.5 psi

Brakes

Brake Caliper Bolt to Carrier TorqueFront: 1LA
Brake Caliper Carrier to Hub Bolt TorqueFront: 1LA
ABS Sensor Torque6.4
Minimum Pad Thickness0.079" in
Vented Rotor Minimum Thickness for ReplacementFront: 1LA; Rear: 1KD

Multi-step torque procedures OEM · verified

Crankshaft Pulley and/or Damper Bolts — tightening sequence 1 stages
1110.0 ft. lbs., Step 2: 150.0 ft. lbs., Step 3: 90°110 ft. lbs
Cylinder Head — tightening sequence 1 stages
1Bolts with Collar37 ft. lbs

Factory maintenance schedule OEM · verified

Normal service, condensed from the factory interval matrix.

Under the factory schedule, replace the engine oil and filter every 10,000 mi; spark plugs every 40,000 mi.

Every 10,000 miBrake Linings (inspect) · Engine Oil (drain & refill) · Engine Oil Filter (replace) · Tire Repair Kit Sealant (inspect)
Every 20,000 miBody Water Drains (inspect) · Brake Line (inspect) · Cabin Air Filter (replace) · Door Hinge (lubricate) · Drive Axle Assembly (inspect) · Engine Assembly (leak inspection)
Every 40,000 miSpark Plugs (replace) · Transmission Assembly (drain & refill)
Every 60,000 miDrive Belt (replace) · Engine Air Filter Element (replace)

Reliability & federal safety record

Owner-reported issues, recalls, investigations and service bulletins on record with NHTSA — an unfiltered look at what owners actually experience.

Owner complaints about the 2021 Audi A4 Quattro lead in one area — the electrical system, 2 of 11 reports (18%), well ahead of the next concern. None of this vehicle's 4 recall campaigns target the electrical system, so those reports read as owner-reported wear-and-tear rather than an acknowledged defect. 3 of the reports describe a crash and 0 a fire — a small share of the total, but worth weighing against the electrical system pattern above. These are tallies of what owners actually reported to the federal government, not an editorial score — and higher-selling models naturally rack up more reports.

4
Open recalls
NHTSA campaigns
1017
Service bulletins
Manufacturer communications
0
ODI investigations
Office of Defects Investigation
11
Owner complaints
3 involved a crash · 0 a fire
NHTSA crash-test rating federal NCAP · out of 5 stars
Overall★★★★★
Frontal★★★★★
Side★★★★★
Rollover★★★★★

Owner complaints filed with NHTSA, by component

All 11 complaints on record, top 8 components.

Electrical System2
Tires1
Power Train1
Unknown Or Other,Lane Departure,Forward Collision Avoidance1
Electrical System,Lane Departure,Forward Collision Avoidance1
Power Train,Unknown Or Other,Engine1
Unknown Or Other1
Suspension,Vehicle Speed Control1

Source: NHTSA Office of Defects Investigation complaint database.

Recalls NHTSA · verified

Showing 2 of 4 campaigns on record for this vehicle.

21V606000Seat Belts:Rear/Other:RetractorReported 05/08/2021

Volkswagen Group of America, Inc. (Volkswagen) is recalling certain 2021 Volkswagen ID4, Audi A4 Allroad, A4 Sedan, A5 Cabriolet, A5 Coupe, A5 Sportback, A6 Allroad, A6 Sedan, A7, A8, E-Tron Quattro, E-Tron Sportback… Remedy: Dealers will inspect, and replace as necessary, the middle-rear seat belt assemblies, free of charge. Owner notification letters were mailed August 27, 2021. Owners may contact…

22V034000TiresReported 26/01/2022

Volkswagen Group of America, Inc. (Audi) is recalling certain 2019-2021 Audi A5 Sportback, RS5 Coupe, RS5 Sportback, S5 Sportback, 2020-2021 A4 Allroad, A4 Sedan, A5 Cabriolet, A5 Coupe, A6 Allroad, A6 Sedan, A7, A8… Remedy: Dealers will inspect the rear axle, adjust the alignment as necessary, and replace any prematurely or unevenly worn tires, free of charge. Owner notification letters were mailed…

Technical service bulletins NHTSA · verified

Showing 5 of 1017 bulletins on record with NHTSA.

BulletinDateComponentSummary
TSB_2078939_22026-06-30EngineThis bulletin provides information when there DTC P218500 is stored in temerature sender…
TSB_2076404_82026-06-29Unknown Or OtherThis bulletin provides a deployment overview for customer service packages MLB and MQB…
TSB_2074640_32026-06-26EngineThis bulletin provides information when there is increased oil consumption; >0.5ltr/1000…
TSB_2074729_32026-06-23Electrical SystemThis bulletin provides informationwhen noises/vibration are detected from front of…
TSB_2059335_72026-06-23Electrical SystemThis bulletin provides information when there are noises from the area around the…

Common OBD-II trouble codes

The most common OBD-II codes for this vehicle's emissions system. These are standardized SAE J2012 definitions, not vehicle-specific fault reports.

P0420
Catalyst system efficiency below threshold — Bank 1
P0300
Random / multiple cylinder misfire detected
P0171
System too lean — Bank 1
P0455
Evaporative emission system leak detected — large leak
P0128
Coolant thermostat below regulating temperature
P0442
Evaporative emission system leak detected — small leak

VIN tools

Decode factory build data for a specific vehicle by VIN.

VIN
Decode a VIN to confirm the transmission and build data for a specific A4 Quattro. OEM
Build data
Plant, GVWR class, engine and body data for any 17-character VIN.
Recalls
Check open recall campaigns against a specific vehicle by VIN.

Vehicles with shared specs

Find every vehicle that shares this one's battery, bulbs, oil capacity, platform or parts.

Group 49 batteryEngine oil filter 06L115562BEngine air filter 8W0133843CSpark plug 06Q905601ABattery 8W0915089A

Reference guides

Cross-vehicle references for the kinds of data on this page.

Vehicle recalls & TSBsOBD-II trouble codesTorque specificationsMaintenance schedulesFluid capacities & specs

Frequently asked

Does the 2021 A4 Quattro have open recalls?

NHTSA lists 4 recall campaign(s) for this model year. Check your specific vehicle by VIN.

What gas mileage does the A4 Quattro get?

EPA figures are 25 city / 34 highway / 28 combined mpg.