Audi A4 [US] / A4 Cabriolet (2008) Wheel Fitment
Audi A4 [US] / A4 Cabriolet (2008): 5x112 bolt pattern, 57.1mm center bore, OE 17x7.5J ET45. Forged wheel fitment specs from ANKUSI.
✓ Verified by ANKUSI's Engineering Team — IATF 16949 & ISO 9001 certified forged wheel manufacturer, TÜV/SFI/VIA compliant. See our factory & certifications →
Wheel Size & Offset at a Glance
| Configuration | Wheel Size & Offset |
|---|---|
| Flush Fitment | 18x8.5J at ET35 offset |
How to Read Wheel Offset & Measurements
Use these two references before ordering: the left diagram shows where each spec (PCD, center bore, offset, width and diameter) is measured on the wheel; the right diagram shows how positive, zero and negative offset shift the wheel face relative to the hub centerline.
ANKUSI Engineering Expert Advice
A sedan's wheel spec is a balance point the factory tuned between ride comfort, steering feel, and everyday durability. Forging lets us hold that same structural margin while cutting rotational mass, which is where most of the real-world benefit — quicker steering response, marginally better ride — actually comes from.
The Audi A4 [US] / A4 Cabriolet ships from the factory on a 5x112 bolt pattern with a 57.1mm center bore and a 17x7.5J ET45 wheel. Our flush reference for the Audi A4 [US] / A4 Cabriolet is 18x8.5J ET35.; our maximum aggressive reference is 19x9J ET32. — beyond that, expect clearance issues against the fender liner without further modification.
Audi A4 [US] / A4 Cabriolet OE Wheel Specs
The Audi A4 [US] / A4 Cabriolet ships from the factory on 5x112 bolt pattern wheels with a 57.1mm center bore. The stock wheel size is 17x7.5J ET45, offering a balanced ride that suits most owners without any rubbing or clearance concerns.
Why the factory spec works for most owners:
- Balances ride comfort with steering response and highway efficiency.
- Wide tire and wheel availability at the factory diameter keeps replacement costs low.
- Lower unsprung weight than larger aftermarket wheels helps ride quality and acceleration.
- Guaranteed clearance against brake calipers and suspension components.
Flush Fitment
For a flush look without any body modification, most Audi A4 [US] / A4 Cabriolet owners run 18x8.5J ET35. This setup tucks the wheel face closer to the fender lip while staying within safe load and clearance limits.
Maximum Aggressive Fitment
Owners chasing a more aggressive stance push to 19x9J ET32. Bilstein B12 Pro-Kit; 18x8.5J ET35 BBS SR wheels; standard brakes; Continental ExtremeContact DWS06 235/40 R18 tires. Note: B7 generation executive compact lineup. Clearance should be verified before ordering, especially on lowered cars.
5-Tier Configuration Options
A – Factory-Style: 17x7.5J ET45
Recommended setup: Factory-matched forged replacement
Economy impact: None
Best for: Daily drivers, warranty-conscious owners
Appearance 5/10 | Comfort 10/10 | Install difficulty ★☆☆☆
Estimated cost range: $$ (OE replacement)
B – Comfortable Upgrade: 17.5x8J ET40
Recommended setup: Direct bolt-on, factory suspension
Economy impact: Minimal
Best for: Owners who want a mild upgrade with no compromise
Appearance 6/10 | Comfort 9/10 | Install difficulty ★☆☆☆
Estimated cost range: $$ - $$$
C – Balanced / Flush Fit: 18x8.5J ET35
Recommended setup: Flush forged wheels, stock or mild lowering
Economy impact: Slight increase
Best for: Enthusiasts wanting a flush look daily
Appearance 8/10 | Comfort 7/10 | Install difficulty ★★☆☆
Estimated cost range: $$$
D – Aggressive: 18.5x9J ET34
Recommended setup: Wider forged wheels, coilovers or lowering springs
Economy impact: Noticeable increase
Best for: Show-and-drive builds
Appearance 9/10 | Comfort 5/10 | Install difficulty ★★★☆
Estimated cost range: $$$$
E – Max Aggressive: 19x9J ET32
Recommended setup: Bilstein B12 Pro-Kit; 18x8.5J ET35 BBS SR wheels; standard brakes; Continental ExtremeContact DWS06 235/40 R18 tires. Note: B7 generation executive compact lineup.
Economy impact: Significant increase
Best for: Show builds, weekend cars
Appearance 10/10 | Comfort 3/10 | Install difficulty ★★★★
Estimated cost range: $$$$$
Performance Comparison Matrix
| Wheel Spec | Tier A | Tier B | Tier C | Tier D | Tier E |
|---|---|---|---|---|---|
| Wheel Spec | 17x7.5J ET45 | 17.5x8J ET40 | 18x8.5J ET35 | 18.5x9J ET34 | 19x9J ET32 |
| Economy Impact | None | Minimal | Slight increase | Noticeable increase | Significant increase |
| Appearance | 5/10 | 6/10 | 8/10 | 9/10 | 10/10 |
| Comfort | 10/10 | 9/10 | 7/10 | 5/10 | 3/10 |
| Install Difficulty | ★☆☆☆ | ★☆☆☆ | ★★☆☆ | ★★★☆ | ★★★★ |
| Cost Range | $$ (OE replacement) | $$ - $$$ | $$$ | $$$$ | $$$$$ |
| Best For | Daily drivers, warranty-conscious owners | Owners who want a mild upgrade with no compromise | Enthusiasts wanting a flush look daily | Show-and-drive builds | Show builds, weekend cars |
Real-World Reference Cases
The following builds are compiled from typical ANKUSI customer configurations for this platform and are illustrative, not individually verified real-world builds.
Case 1: Daily Driver (Factory-Style)
Profile: Commuter prioritizing comfort and reliability.
Setup: 17x7.5J ET45 forged wheels, factory suspension.
Cost: $$ (OE replacement)
Outcome: No clearance issues, factory ride quality retained.
Case 2: Balanced Enthusiast (Balanced / Flush Fit)
Profile: Weekend driver wanting a flush stance without sacrificing daily usability.
Setup: 18x8.5J ET35 forged wheels, mild lowering springs.
Cost: $$$
Outcome: Flush fitment with acceptable ride comfort for daily use.
Case 3: Show Build (Max Aggressive)
Profile: Show-and-shine build prioritizing stance over comfort.
Setup: 19x9J ET32 forged wheels. Bilstein B12 Pro-Kit; 18x8.5J ET35 BBS SR wheels; standard brakes; Continental ExtremeContact DWS06 235/40 R18 tires. Note: B7 generation executive compact lineup.
Cost: $$$$$
Outcome: Maximum aggressive stance; clearance verified case-by-case.
Decision Guide
Offset & Backspacing Reference
Backspacing is calculated as: wheel width (in) / 2 + offset (mm) / 25.4 + 0.5.
- OE 17x7.5J ET45: backspacing ≈ 6.02"
- Flush 18x8.5J ET35: backspacing ≈ 6.13"
- Max 19x9J ET32: backspacing ≈ 6.26"
Use our offset & backspacing calculator to fine-tune your fitment, or contact ANKUSI for a custom forged wheel quote for your Audi A4 [US] / A4 Cabriolet.
Frequently Asked Questions
What bolt pattern (PCD) does the Audi A4 [US] / A4 Cabriolet use?
How many lug bolts does the Audi A4 [US] / A4 Cabriolet use?
What does a flush wheel fitment look like on the Audi A4 [US] / A4 Cabriolet?
Do I need wheel spacers for my Audi A4 [US] / A4 Cabriolet?
How do I calculate wheel backspacing for my Audi A4 [US] / A4 Cabriolet?
What's the difference between wheel offset and backspacing?
Can I run staggered wheels (different sizes front and rear) on my Audi A4 [US] / A4 Cabriolet?
Wheel Installation Reference: Torque, Thread & TPMS
Thread & Fastener: M14x1.5, ball-seat lug bolt (13mm radius).
Factory Torque Spec: 120 Nm (89 ft-lb). Shared VW/Audi Group ball-seat bolt spec used across most 5x112 Audi models.
TPMS: TPMS (Tire Pressure Monitoring System) has been federally mandated on all new light vehicles sold in the US since the 2008 model year. If your wheels use OE-style sensors, have them transferred or cloned to the new wheels at installation.
Tire Pressure: Always set tire pressure to the value on your vehicle's tire placard (driver's doorjamb or glovebox), not the max PSI printed on the tire sidewall — this is trim- and tire-size-specific and stays the same reference point when you switch to a different wheel and tire combination.
Reference data compiled from published OEM service specifications and cross-checked against independent repair sources; always confirm against your owner's manual or door-jamb placard before installation.