What Size Are Audi Lug Nuts?

Most modern Audi models use lug bolts (not traditional “nuts”) with an M14 x 1.5 thread and a 17 mm hex head, but some older and smaller models use M12 x 1.5. Exact size depends on model and year, and drivers should always confirm using the owner’s manual, parts catalog, or by checking the existing hardware.

Understanding Audi Wheel Fasteners: Lug Bolts, Not Lug Nuts

The question “What size are Audi lug nuts?” is slightly misleading, because almost all Audi vehicles use lug bolts that screw directly into the hub rather than lug nuts threaded onto studs. This construction detail affects not only the size you need for replacements or aftermarket wheels, but also the tools and torque settings you should use.

Lug Bolts vs. Lug Nuts

On many American and Japanese vehicles, the wheels are secured with lug nuts that thread onto fixed studs sticking out of the hub. Audi (and most other Volkswagen Group brands) instead use individual bolts that thread into the hub itself. For practical purposes, people still call them “lug nuts,” but when buying parts or reading technical info, the correct term is “lug bolts.”

Common Audi Lug Bolt Sizes by Generation and Platform

While there is variation across decades and platforms, Audi uses a relatively small set of standard sizes. This makes it easier to identify likely dimensions based on model family and age, though you should still verify for your specific car.

Typical Thread Sizes

The most important dimensions for identifying “what size” lug hardware are the thread diameter and pitch. For Audi, two thread sizes dominate: M14 x 1.5 and M12 x 1.5.

The following list outlines the most common thread sizes used on Audi passenger vehicles and SUVs.

• M14 x 1.5 – The most common size on modern Audi models, especially from roughly the mid‑2000s onward, including many A4, A5, A6, A7, A8, Q3, Q5, Q7, Q8, and performance S/RS variants.
• M12 x 1.5 – More common on older or smaller Audi models, especially earlier A3 and some older compact-platform cars, as well as certain 1990s models.

These two sizes cover the overwhelming majority of factory Audi applications; however, exact usage can vary by model year, trim, and platform updates, so confirming on your specific vehicle remains essential.

Hex (Socket) Size

Besides thread dimensions, you also need the hex size (the wrench or socket that fits the head of the bolt). For recent Audi vehicles, the standard wheel bolt head is typically 17 mm.

The following list summarizes the most common hex sizes on Audi wheel bolts.

• 17 mm hex head – Most modern Audi models, including A‑series sedans, S/RS models, and SUVs, use a 17 mm wheel bolt head.
• 19 mm hex head – Found on some older models or certain aftermarket wheel bolt sets; not as common on current factory setups.

In practice, a 17 mm socket is usually what you’ll find in an Audi’s factory tool kit, indicating the hex size you need for the standard wheel bolts.

Typical Audi Wheel Bolt Dimensions in Detail

When owners ask for “lug nut size,” they may actually care about multiple dimensions: thread size, seat type, shaft length, and head size. Each matters for safe wheel installation and compatibility with aftermarket wheels.

Thread Diameter and Pitch

For most modern Audi passenger vehicles:

The following list clarifies what the common Audi thread designations mean.

• M14 x 1.5 – 14 mm major thread diameter with a 1.5 mm thread pitch (distance between threads). This is now the dominant size for medium and large Audi platforms and performance models.
• M12 x 1.5 – 12 mm major thread diameter with a 1.5 mm thread pitch. More often seen on older or smaller cars, especially pre‑mid‑2000s and some early A3 / compact models.

Using the wrong thread size can damage the hub or bolts and compromise wheel retention, which is why verifying the exact specification before purchase or installation is critical.

Seat Type: Ball vs. Conical

Audi factory wheels overwhelmingly use a ball (radius) seat rather than a conical (tapered) seat, which is common on many aftermarket wheels. Using the wrong seat style can prevent full contact, leading to loosening or damage.

The following list outlines the two main seat styles you will encounter with Audi wheels.

• Ball seat (radius seat) – Standard on most OEM Audi wheels. The base of the bolt head is rounded to match a spherical recess in the wheel.
• Conical (tapered) seat – Common on many aftermarket wheels; requires bolts specifically designed with a conical taper to match the wheel’s seat.

If you install aftermarket wheels on an Audi, you may need to switch from OEM ball-seat bolts to conical-seat bolts to match the wheel manufacturer’s design.

Shank (Bolt) Length

The overall length of the bolt, and especially the length of the threaded shank, must be appropriate for your wheel thickness and any spacers you use. While the exact length varies by model and wheel design, the factory bolts are engineered to provide the correct engagement in the hub.

The following list summarizes key length considerations.

• Factory bolt length – Designed to give sufficient thread engagement (typically around 7–9 full turns) with stock wheels and no spacers.
• Longer bolts – Required if you add wheel spacers; the bolt must be longer by roughly the thickness of the spacer while maintaining adequate engagement.
• Aftermarket wheel thickness – Some wheels have thicker mounting pads, which may necessitate a longer bolt to maintain safe engagement.

Insufficient thread engagement can lead to bolt failure or wheel loss; excessively long bolts can bottom out or damage internal components such as parking brake hardware.

Model‑Specific Tendencies (Approximate)

Because Audi shares platforms across multiple models, many vehicles within a given family will use the same lug bolt size. Still, owners should treat any such information as indicative rather than definitive.

A-Series Sedans and Sportbacks (A3, A4, A5, A6, A7, A8)

Across the A‑series, Audi has gradually standardized on larger M14 hardware as vehicles grew heavier and tire sizes increased.

The following list describes common tendencies by segment and era.

• A3 / S3 / RS 3 – Earlier generations more likely to use M12 x 1.5; later MQB‑based and current models typically M14 x 1.5 with 17 mm hex, ball seat.
• A4 / S4 / RS 4 (B6 onward) – Generally M14 x 1.5, ball seat, 17 mm hex on modern generations.
• A5 / S5 / RS 5 – Typically M14 x 1.5, ball seat, 17 mm hex across recent generations.
• A6 / S6 / RS 6 – M14 x 1.5 is standard on modern C6, C7, and later platforms, with ball-seat bolts and 17 mm hex.
• A7 / S7 / RS 7 – Shares hardware characteristics with contemporary A6 platforms: M14 x 1.5, ball seat, 17 mm hex.
• A8 / S8 – As a larger flagship sedan, these models have long used robust M14 x 1.5 hardware on recent generations.

Within any specific platform, special editions or performance variants usually keep the same thread size but may differ in bolt length due to wheel design.

Q-Series SUVs (Q3, Q4 e‑tron, Q5, Q7, Q8, e‑tron SUV)

Heavier SUVs rely on larger-diameter fasteners to safely handle higher loads, and Audi’s Q‑series reflects this with widespread use of M14 bolts.

The following list highlights general patterns for Audi SUVs.

• Q3 – Earlier generations may use M12 x 1.5; newer models and many performance trims move to M14 x 1.5.
• Q4 e‑tron – Typically uses M14 x 1.5 bolts with ball seats, reflecting EV weight and platform needs.
• Q5 / SQ5 – Commonly M14 x 1.5 with 17 mm hex on most modern generations.
• Q7 / SQ7 / Q8 / SQ8 / RS Q8 – Larger, heavier SUVs and performance variants consistently use M14 x 1.5, ball seat, and 17 mm hex, often with longer bolt lengths to suit wide wheels.

Electric and plug‑in hybrid variants generally follow the same pattern as their ICE-based platforms, but confirmation via parts documentation is still recommended.

How to Confirm the Exact Lug Bolt Size on Your Audi

Because production changes and regional variations exist, the only reliable way to know your exact hardware specifications is to check documentation or measure directly. This minimizes the risk of ordering incorrect parts or installing incompatible bolts.

Checking Documentation and Factory Labels

Audi provides several information sources that can help owners verify correct wheel fastener sizes for their vehicle.

The following list outlines the most reliable ways to confirm your lug bolt size without disassembling anything.

• Owner’s manual – Often specifies wheel bolt thread size and torque specification; look in the “Wheels and Tires” or “Changing a Wheel” section.
• Factory tool kit – The size of the included wheel wrench or socket (commonly 17 mm) tells you the bolt head size, though not the thread diameter.
• Dealer or OEM parts catalog – Providing your VIN to an Audi dealer or using an online OEM catalog will return the exact part number and dimensions of the factory wheel bolts.
• Service information systems – Professional repair databases (such as Audi’s official ErWin service portal) list thread sizes and torque values by model and year.

These official sources are preferred over generic web tables, which may aggregate data without accounting for mid‑cycle updates or regional differences.

Measuring Existing Hardware

If documentation is unavailable, a careful measurement of your existing bolts can confirm size and compatibility for replacements or aftermarket wheels.

The following list describes practical steps for measuring an Audi wheel bolt.

• Remove one wheel bolt – Loosen with the correct socket (usually 17 mm) and remove a single bolt from the wheel for inspection.
• Measure thread diameter – Use a caliper to measure the diameter of the threaded portion; values near 14 mm indicate M14, near 12 mm indicate M12.
• Check thread pitch – Use a thread pitch gauge; for Audi, you will typically find 1.5 mm pitch on both M12 and M14 bolts.
• Measure bolt length – Measure from the underside of the head to the end of the threads; compare to OEM specifications, especially if spacers or aftermarket wheels are used.
• Identify seat type – Visually inspect the shape under the head: a rounded contour suggests a ball seat, a straight taper suggests a conical seat.

Accurate measurements ensure that any replacement or upgraded hardware matches the mechanical and safety requirements of your vehicle and wheels.

Torque Specifications and Safety Considerations

Knowing lug bolt size is only part of safe wheel installation; correct torque and seating practice are equally important. Over‑ or under‑tightening can damage components or allow the wheel to work loose over time.

Typical Audi Wheel Bolt Torque Ranges

Most modern Audi models specify wheel bolt tightening torques in the area of 120–150 Nm (around 89–111 lb‑ft), typically near the lower end of that range for standard passenger models. Exact values depend on platform, wheel size, and model year.

The following list summarizes common practices around torque and tool use.

• Use a calibrated torque wrench – Set to the torque specified in your owner’s manual or service documentation; avoid relying solely on impact guns.
• Tighten in a star pattern – When re‑installing wheels, tighten bolts in a cross or star sequence to ensure the wheel seats evenly.
• Re‑check after driving – After installing wheels (especially with new hardware or spacers), re‑torque bolts after 50–100 km (30–60 miles).
• Clean threads and seats – Remove corrosion and dirt; avoid lubricants unless specifically recommended, as they can alter friction and torque readings.

Proper torque and clean, correctly matched hardware help prevent vibration, uneven wear, and potentially dangerous wheel loosening.

Aftermarket Wheels, Spacers, and Locking Bolts

Many Audi owners upgrade their wheels or add spacers for stance and fitment reasons. These modifications can change the required lug bolt dimensions and seat style, and getting this wrong is one of the most common causes of fitment complaints.

Matching Hardware to Aftermarket Wheels

When switching from OEM to aftermarket wheels, you often need to change from ball-seat to conical-seat bolts, adjust bolt length, or both.

The following list highlights key compatibility checks for aftermarket setups.

• Confirm seat style with the wheel manufacturer – Do not assume; many aftermarket wheels use conical seats, even for Audi applications.
• Adjust bolt length for spacers – Add the spacer thickness to your OEM threaded engagement; use appropriately longer bolts that still seat correctly.
• Maintain correct thread size – Always retain the vehicle’s hub thread (M14 x 1.5 or M12 x 1.5); never attempt to force mismatched hardware.
• Use quality locking bolts – Locking (anti‑theft) bolts should match the correct size and seat type; avoid mixing different seat styles on the same wheel.

Taking time to confirm these details prevents issues such as wheel wobble, bolt loosening, or hub damage that can emerge after seemingly minor changes.

Summary

Most current Audi vehicles use wheel bolts rather than traditional lug nuts, with the predominant size being M14 x 1.5 thread and a 17 mm hex head, paired with a ball-seat design. Some older or smaller models, particularly early A3s and certain 1990s platforms, use M12 x 1.5 hardware. Exact dimensions—including thread size, seat type, and bolt length—vary by model, year, and wheel design, and must be confirmed via the owner’s manual, OEM parts data, or direct measurement. Using the correct size and seat style, along with proper torque procedures, is essential for safe and reliable wheel installation on any Audi.

What size are Audi wheel bolts?

Most modern Audi models use M14x1.5 wheel bolts with a 17mm hex head and a ball or radius seat. The exact shank length can vary, but common lengths are 27mm or 28mm. For some older or 4-lug models, a smaller M12x1.5 size may be used instead. 
Common specifications for most Audi models

• Thread size: M14x1.5 
• Hex size: 17mm (except for some e-tron models, which use a 19mm hex) 
• Seat type: Ball (radius) seat is standard for factory wheels. Aftermarket wheels might require a cone (conical) seat 
• Shank length: Commonly 27mm or 28mm, but this can vary by model year 

Other sizes

• M12x1.5: Used for some older 4-lug Audi and Volkswagen models 

Important considerations

• Always confirm the correct size for your specific vehicle model and year before purchasing new bolts, notes Amazon.com and Advance Auto Parts 
• Ensure the seat type (ball or cone) matches your wheels to prevent damage and ensure a secure fit, say this YouTube video and Amazon.com 

What size lug nuts on Audi?

Audi/Volkswagen 40mm (14mm Diameter) Lug Bolts (Qty: 10) – Raceland.

What size are the lug nuts on a 2012 Audi a7?

14 mm x 1.5 thread size, 17 mm hex, 1.55″ shank length.

What size are the lug nuts on a 2018 Audi?

14 mm x 1.5 thread size, spline lug bolt, 1.1″ length.