2009 Audi A5 Wheel Interchange
OEM wheel/tire sizes and fitment specs for the 2009 Audi A5.
2009 Audi A5 Wheel Fitment and Interchange Guide | wheelinterchange.com
1. Goal
You need to know which wheels and tires will fit your 2009 Audi A5 without rubbing, vibration, or speedometer issues. This guide starts from the practical problem. We will use the on-page calculator to compare options, explain the trade-offs, and validate against OEM baselines.
2. Prerequisites
- Confirm your exact trim and brake package. Some A5 models use larger brakes. Clearance can change. If unsure, measure caliper clearance directly.
- Know your current tire and wheel sizes from the sidewall and wheel stampings.
- Have basic tools for safe installation. A torque wrench is recommended for final tightening 1/2 inch drive torque wrench. A wheel hanger guide pin helps on Audi’s lug bolts M14x1.5 wheel hanger guide pin. A caliper helps measure bores and spacers digital caliper.
- Assumption: the baseline values below represent a common OEM setup. Some markets or trims may differ. Use the calculator and your owner’s manual for final validation.
Known OEM baseline for 2009 Audi A5
| Bolt pattern | 5x112 |
| Center bore | 66.6 mm |
| Thread size | M14 x 1.5 (lug bolts) |
| Rim diameter | 17 in |
| Rim width | 7.5 in |
| Wheel offset (ET) | 28 mm |
| Backspacing | 4.85 in |
| Tire size | 225/50R17 |
Approximate OEM tire diameter calculation for comparison: 225/50R17 gives a sidewall of 112.5 mm. Overall diameter is roughly 25.9 inches. The calculator will handle this math for each size you test.
3. Step by step
We will use the calculator to test interchange, visualize clearance, and plan a safe setup.
- Set Installed on to your vehicle: 2009 Audi A5. The baseline above should prefill. If your car differs, adjust to match your actual current setup.
- Pick a Wheels from donor vehicle to compare. Do not rely on bolt pattern alone. Interchange depends on offset, width, center bore, and hardware too.
- Open Custom wheel size. Change rim diameter, width, and offset to the donor or aftermarket specs. Watch inner clearance and outer poke in the results.
- Open Custom tire size. Adjust section width and aspect ratio. The tool updates total tire diameter as you change rim diameter. Keep overall diameter close to OEM. A commonly recommended tolerance is about 2 to 3 percent, depending on your constraints.
- Center bore check. Your hub is 66.6 mm. If a wheel’s center bore is larger, you will need hub-centric rings sized to 66.6 mm on the hub side 66.6 hub-centric rings. If the bore is smaller than 66.6 mm, that wheel will not seat without machining.
- Hardware check. Audi uses M14x1.5 lug bolts. Match the seat style to the wheel. Many OEM wheels use a ball seat, while many aftermarket wheels use a cone seat. Confirm with the wheel maker and your manual.
- Brake clearance. Use the calculator’s inner clearance view as a first pass. If you have a larger brake package, leave margin. When possible, test fit or use a caliper template from the wheel manufacturer.
4. Validation
Before purchasing, run these checks to reduce risk.
- Offset and backspacing sanity check. For the OEM 7.5J ET28 wheel: half width is 3.75 inches. ET28 equals 1.10 inches. 3.75 plus 1.10 equals 4.85 inches of backspacing, which matches the baseline. Use the same math to validate candidate wheels.
- Clearance measurement. With the car on the ground, place a straight edge along the fender and measure outward poke change from the calculator. Inside, measure strut and liner clearance. Leave a safety margin for bushing deflection.
- Diameter check. Compare the calculator’s overall tire diameter to the OEM value. Keep within your comfort range to protect ABS, speedometer accuracy, and gearing.
- Test fit if possible. Spin the wheel by hand and turn lock to lock. Check caliper, knuckle, and liner clearance under compression.
- Installation practice. Tighten lug bolts in a star pattern and torque to the OEM specification listed in your manual. Re-torque after a short drive cycle torque wrench.
5. Troubleshooting
- Vibration at speed. Likely hub-centric issue or balance. Use proper rings to 66.6 mm and request a road-force balance. Inspect for bent wheels or uneven tire wear.
- Rubbing on fender or liner. Reduce width or aspect ratio, or select a higher offset to pull the wheel inward. If inner rub occurs on the strut, a small spacer can help, but that requires longer lug bolts and new validation. Keep the change minimal and confirm thread engagement equals the OEM standard. When in doubt, consult the service manual.
- Lug bolt mismatch. Do not mix seat styles. Ball seat bolts in a cone seat wheel, or vice versa, can loosen. Match M14x1.5 and the correct seat exactly.
- Center bore mismatch. Smaller than 66.6 mm will not fit. Larger needs rings to avoid vibration
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