2018 Audi TT Wheel Interchange

2018 Audi TT Wheel Fitment Guide | wheelinterchange.com

Known OEM Fitment For 2018 Audi TT

The values below reflect an OEM configuration provided for the 2018 Audi TT. Other trims or option packages may differ. If your car is a TTS, TT RS, or a special package, verify your exact fitment using your door jamb tire placard, owner’s manual, or an OEM parts catalog by VIN.

If your OEM size does not match the table, use the calculator on this page to compare your current setup to any potential donor wheels. Always confirm with OEM documentation before purchase.

How To Use The Wheel Interchange Calculator

The calculator lets you compare donor wheels to your 2018 Audi TT and test custom wheel and tire sizes. It shows changes in poke, inner clearance, and overall tire diameter so you can predict fender and suspension clearance.

• Set Installed on (your vehicle) to 2018 Audi TT. Enter your current OEM values if needed: 18x8.5 ET50 with 245/40R18.
• Choose Wheels from (donor vehicle) or manually enter a Custom wheel size. You can change rim diameter, width, and offset, then set a Custom tire size.
• Watch how offset and width affect:
  • Outer position (poke) which affects fender and arch clearance.
  • Inner clearance which affects strut, spring perch, and liner clearance.
  • Tire diameter which affects speedometer and ABS tolerance.
• Use the tire field to keep overall diameter close to stock. A common guideline is to stay within about plus or minus 2 to 3 percent of OEM overall diameter.
• If you change rim diameter, the comparison updates tire diameter automatically when you select a matching tire size.
• Record any predicted changes, then verify physically with a test fit where possible.

Fitment Checklist Before You Buy

• Bolt pattern: Must be 5x112.
• Center bore: Vehicle is 57.1 mm. If the wheel’s bore is larger, use hub-centric rings to 57.1 mm. Do not use a wheel with a bore smaller than 57.1 mm.
• Seat type: Match your lug bolt seat to the wheel seat. Many OEM Audi wheels use a ball seat and many aftermarket wheels use a cone seat. Confirm visually or with the seller. Do not mix seat types.
• Thread size and engagement: M14 x 1.5. Ensure sufficient thread engagement. A common engineering guideline is engagement at least equal to the bolt diameter (about 14 mm) once tightened.
• Offset and width: Use the calculator to compare to OEM 18x8.5 ET50. Ensure:
  • Inner clearance remains safe to strut, control arms, and liners. Aim for a few millimeters margin at minimum.
  • Outer poke does not contact fender or bumper liners over bumps and during steering.
• Brake caliper and spoke clearance: Spoke design matters. Calculator shows position, but caliper shape is 3D. Test fit when possible.
• Tire overall diameter: Keep close to OEM to protect ABS and speedometer accuracy.
• TPMS: System type and requirements can vary by trim and market. Check your owner’s manual for reset or sensor needs.
• Spacers and extended bolts: If you add spacers, use hub-centric spacers and the correct longer M14 x 1.5 bolts. Length increase generally equals spacer thickness.

Plus Sizing And Common Upgrades

Enthusiasts often explore larger diameters or wider wheels. Because trim packages can vary, treat the ideas below as examples only. Always simulate your exact sizes with the calculator and verify in person.

• Wider tires on 18-inch wheels: For a sportier stance, compare widths around 8.5 to 9.5 inches with offsets that maintain inner clearance and keep outer poke reasonable. Use the calculator to predict changes from 18x8.5 ET50 and 245/40R18.
• Upsizing diameter: If considering 19-inch or 20-inch, choose tire aspect ratios that keep overall diameter close to stock. Confirm fender clearance on compression and full steering lock.
• Brake clearance: Larger brakes on performance trims may need specific spoke shapes. Even if the diameter and offset look fine, spoke-to-caliper clearance can be the deciding factor.
• Ride quality: Lower-profile tires reduce sidewall compliance. Expect more road feel and possible tramlining compared to the 245/40R18 OEM example.

Installation Tips

• Clean hub faces and wheel mounting pads until bare metal is visible. Any rust or debris can cause runout.
• Dry-fit first. Spin the wheel by hand to check for inner interference before lowering the car.
• Use the correct seat-style lug bolts and verify thread engagement by hand before applying final torque.
• Tighten bolts in a star pattern in stages. Refer to the owner’s manual or service information for the specified torque for your trim. Do not guess the torque.
• If using spacers, confirm hub-centric fitment on both sides and use appropriate extended M14 x 1.5 bolts.
• After 50 to 100 miles, recheck bolt torque on cool wheels.
• TPMS: Follow the procedure in your owner’s manual for reset or sensor pairing if applicable.

Tools And Helpful Supplies

• 1/2 inch drive torque wrench
• Thin wall 17 mm and 19 mm socket set
• Wheel hanger guide pin M14 x 1.5 for easier mounting
• Hub-centric rings to 57.1 mm if your aftermarket wheel bore is larger

FAQs

• What is the bolt pattern for the 2018 Audi TT?

  5x112 based on the known OEM specification provided.

• What is the center bore for the 2018 Audi TT?

  57.1 mm. Use hub-centric rings if your wheel bore is larger. Do not use a wheel with a smaller bore.

• What lug hardware does it use?

  M14 x 1.5 lug bolts. The seat type must match the wheel. Many OEM Audi wheels use ball seats and many aftermarket wheels use cone seats. Confirm before installation.

• What is the OEM wheel and tire size?

  An OEM example is 18x8.5 ET50 with 245/40R18. Your trim may differ. Check your door placard or owner’s manual and compare in the on-page calculator.

• Will wheels from another Audi fit my 2018 TT?

  Only if key specs align. Match 5x112 bolt pattern, center bore at least 57.1 mm, appropriate offset and width that maintain inner and outer clearances, and correct seat-style hardware. Use the calculator to compare, then test fit.

• Can I run spacers on the 2018 TT?

  Yes, if needed for clearance. Use hub-centric spacers and longer M14 x 1.5 bolts matched to spacer thickness. Verify fender and inner clearances with the calculator and a test fit.

• How close should my new tire diameter be to stock?

  A common guideline is within about 2 to 3 percent of OEM overall diameter. This helps keep speedometer and ABS behavior predictable.

• What torque should I use on the lug bolts?

  Consult the owner’s manual or factory service information for your specific trim. Do not guess the torque value.

• Do I need to modify TPMS when changing wheels?

  Depends on your vehicle’s TPMS type and market. Some systems require a reset, others may need sensors transferred or programmed. Check your owner’s manual.