OEM wheel and tire fitment specs for the 2018 Cadillac CTS, including bolt pattern (PCD), center bore diameter, thread size, rim diameter, rim width, wheel offset, and backspacing.
Recorded OEM specifications for the 2018 Cadillac CTS, donor years with overlapping ranges, and a calculator to compare a selected wheel. Range overlap is not a guaranteed fit.
Multiple OEM configurations exist for this vehicle. Fitment can vary by trim, brakes, and factory wheel package – confirm your exact setup before buying.
Thread-only product links are shopping examples, not verified fits. Seat style is not confirmed here. As an Amazon Associate we earn from qualifying purchases.
Donor vehicles with overlapping OEM specs
These are vehicle-year records whose recorded OEM ranges overlap this 2018 Cadillac CTS. Overlap is not a guarantee that a specific wheel will install. Selected-wheel comparison is in the calculator below.
Evaluated 39 donor years. Listed 24 eligible overlaps (not all evaluated years are compatible). Showing all listed.
Wheel geometryOEM width/offset ranges overlap (not a specific wheel)
Approximate position vs the mid OEM package: outer change -3.5 mm, inner change 3.5 mm. This uses aggregated width/offset ranges, not a specific wheel.
Check wheel configurationCheck lug hardware: donor year M12x1.5 vs 2018 Cadillac CTS M14x1.5
Bolt pattern5x120 · Same recorded PCD
Center bore70.3 mm donor vs hub 66.9 mm
Wheel geometryNeeds configuration check
Recorded vehicle-side thread for the 2018 Cadillac CTS is M14x1.5. This donor year is recorded as M12x1.5. That is the vehicle stud/nut thread, not an intrinsic thread stamped on the wheel. Hardware must match this vehicle’s studs and the selected wheel’s seat and engagement. Existing hardware may be reusable if it already matches. Seat style is not in this dataset, so products are not a verified fit.
Dataset suggestionHub-centric rings ≈ 70.3 → 66.9 mm – not a verified installation requirement.
Hub-centric rings of about 70.3 → 66.9 mm mm may be relevant if the wheel bore is larger than the hub; clearance is not verified. Donor width/offset sits outside the known OEM envelope for this vehicle.
Dataset suggestionWheel spacer ≈ 17.85 mm – not a verified installation requirement.
A spacer of about 17.85 mm is a dataset suggestion only; clearance is not verified. Estimated outer position is about 17.85 mm farther inward than the mid OEM package.
OEM specs overlapOEM ranges overlap – confirm the specific wheel
Bolt pattern5x120 · Same recorded PCD
Center bore66.9 mm · same recorded hub figure
Wheel geometryOEM width/offset ranges overlap (not a specific wheel)
Recorded OEM bolt pattern, center bore, and width/offset ranges overlap. This is not a guarantee that every wheel from the donor year fits this vehicle.
Wheel geometryOEM width/offset ranges overlap (not a specific wheel)
Approximate position vs the mid OEM package: outer change -6.85 mm, inner change -5.85 mm. This uses aggregated width/offset ranges, not a specific wheel.
OEM specs overlapOEM ranges overlap – confirm the specific wheel
Bolt pattern5x120 · Same recorded PCD
Center bore66.9 mm · same recorded hub figure
Wheel geometryOEM width/offset ranges overlap (not a specific wheel)
Recorded OEM bolt pattern, center bore, and width/offset ranges overlap. This is not a guarantee that every wheel from the donor year fits this vehicle.
Wheel geometryOEM width/offset ranges overlap (not a specific wheel)
Recorded OEM bolt pattern, center bore, and width/offset ranges overlap. This is not a guarantee that every wheel from the donor year fits this vehicle.
Wheel geometryOEM width/offset ranges overlap (not a specific wheel)
Recorded OEM bolt pattern, center bore, and width/offset ranges overlap. This is not a guarantee that every wheel from the donor year fits this vehicle.
Cadillac CTS Years With Compatible Wheels
Only years with evidence-based interchange relationships are listed. Adjacent years are not assumed compatible.
Compare a donor vehicle or custom wheel against this 2018 Cadillac CTS. Use Compare in calculator on a donor row above to fill the donor side of this same calculator.
Compare
Compare wheel compatibility between two vehicles
Wheels from (donor vehicle)
Selected Car:
Custom wheel size (optional)
Tip: change values here to simulate custom wheels and immediately see the impact in the comparison below.
Custom tire size (optional)
Installed on (your vehicle)
Selected Car:
2018 Cadillac CTS
Compare Rims
Specification
Wheels from
Installed on
Result (Click it)
Bolt Pattern
The total number of bolt holes and the diameter of the circle they form.
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5x120
Center Bore
The hole in the center of the wheel that fits over the vehicle’s hub.
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66.9 mm
Thread Size
The size and spacing of the threads on the bolts or nuts that hold the wheel in place.
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M14 x 1.5
Rim Diameter
The wheel diameter in inches that determines which tire sizes will fit.
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17"
Rim Width
The distance between the inner edges of the wheel is measured in inches.
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8.5"
Wheel Offset
How far the wheel sits inward or outward relative to the hub mounting surface.
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32 mm
Backspacing
Shows how much space the wheel takes up toward the inside of the vehicle.
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-
Wheel Fasteners
The type of hardware used to secure the wheel to the vehicle.
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-
Compare Tires
Specification
Wheels from
Installed on
Result (Click it)
Section Width
The width of the tire from sidewall to sidewall, measured in millimeters.
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-
Aspect Ratio
The height of the tire’s sidewall expressed as a percentage of its width.
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-
Diameter
The wheel diameter for which the tire is designed to fit.
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-
Tire Pressure
The recommended air pressure for safe and efficient driving.
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-
Overall Diameter
The total height of the tire and wheel combined affects clearance and speedometer accuracy.
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-
Wheel Fitment Parts for the 2018 Cadillac CTS
Example products matched to recorded thread, hub, or spacer dimensions. They are not verified fits. Confirm seat style, thickness, and clearance before ordering.
As an Amazon Associate we earn from qualifying purchases. Product availability and pricing may change.
2018 Cadillac CTS Wheel Interchange and Fitment Guide
Known OEM Fitment For 2018 Cadillac CTS
The information below reflects verified data available for the 2018 Cadillac CTS. This model was offered with multiple factory wheel and tire packages. The wheel and tire entries provided here may come from different OEM packages. Always confirm what your specific trim and brake package uses by checking your driver door jamb tire placard, your owner manual, or OEM service information, then validate in the on-page calculator.
Bolt pattern
5x120
Center bore
66.9 mm
Thread size
M14 x 1.5
Known OEM wheel size
19 x 8.5
Offset (ET)
34 mm
Backspacing
5.59 in
Known OEM tire size
245/45R17
Notes:
The listed 19 x 8.5 ET34 wheel and the 245/45R17 tire are from different factory configurations. Not all trims will clear 17 inch wheels. Verify your brake rotor and caliper size before using 17 inch wheels.
If any specification you need is not listed or varies by trim, use the calculator on wheelinterchange.com and cross-check against OEM sources.
How To Use The Wheel Interchange Calculator
Open the calculator and select your donor vehicle in Wheels from and your 2018 Cadillac CTS in Installed on.
If you are testing aftermarket wheels, use Custom wheel size to enter rim diameter, rim width, and offset. You can also enter Custom tire size to compare overall diameter and sidewall changes.
Changing rim diameter updates the tire diameter comparison. Keep the overall tire diameter close to your OEM package to protect ABS, traction control, and speedometer accuracy.
Review inner clearance to the strut or knuckle and outer clearance to the fender and liners. Compare the new backspacing and poke to the OEM reference of 5.59 in backspacing for the listed 19 x 8.5 ET34 wheel.
Check scrub radius changes by monitoring how much offset you add or subtract from the OEM ET34 baseline. Large jumps can affect steering feel and bearing load.
When results look acceptable in the calculator, confirm physically before driving: test-fit one front and one rear wheel, rotate by hand, and inspect for interference.
Fitment Checklist Before You Buy
Bolt pattern: 5x120 must match exactly.
Center bore: 66.9 mm hub. If the wheel center bore is larger, use hub-centric rings sized 66.9 mm inner to your wheel’s outer bore. Do not use a wheel with a smaller bore unless it is professionally machined.
Offset: Start from the known OEM ET34 for the 19 x 8.5 reference. Use the calculator to evaluate how moving offset in or out changes inner and outer clearance.
Backspacing: Compare new backspacing to the 5.59 in OEM reference to understand inner clearance changes.
Brake clearance: The CTS had multiple brake packages. Visually confirm spoke-to-caliper and barrel-to-caliper clearance. Some packages may not clear 17 inch wheels.
Lug hardware: Thread is M14 x 1.5. Verify that the lug seat style on your wheel matches your lugs or nuts. Do not mix conical, ball, or mag seats.
Tire overall diameter: Keep overall diameter close to your OEM package to avoid speedometer and ABS issues. Use the calculator to compare.
Load and speed ratings: Tires and wheels must meet or exceed the OEM load index and speed rating listed on your door placard.
TPMS: Plan to transfer, clone, or program sensors compatible with your CTS. Verify compatibility with your sensor vendor or OEM parts catalog.
Plus Sizing And Common Upgrades
Plus sizing changes wheel diameter and tire profile to maintain overall tire diameter while improving appearance or handling. General guidance:
Use the OEM package for your trim as the baseline. The provided data includes a 19 x 8.5 ET34 wheel and a separate OEM tire size of 245/45R17 from another package. Confirm which your CTS actually uses.
Aim to keep overall tire diameter within a small variance of your OEM package. Use the calculator to target a minimal difference.
Maintain similar offset to control scrub radius and bearing load. Large offset changes can cause rubbing or premature wear.
Staggered setups can affect rotation patterns and tire wear. Confirm rear clearance and load index if considering wider rears.
Low-profile tires increase impact risk. Consider your road conditions and ride goals before stepping down in sidewall height.
Installation Tips
Test fit first. Mount a front and rear wheel without tires where possible, or carefully check with tires for caliper and fender clearance. Spin by hand and compress the suspension if you can.
Clean the hub face and the wheel mounting pad. Remove rust and debris to ensure the wheel seats flat and runs true.
Use hub-centric rings if the wheel bore is larger than 66.9 mm. Ensure rings seat fully on the hub and in the wheel.
Verify thread engagement. For M14 studs or bolts, ensure sufficient full turns of engagement. If using spacers, use longer hardware as required.
Hand start all lugs, snug in a star pattern, then torque with a calibrated torque wrench to the value in your owner manual or OEM service information. Do not rely on impact tools for final torque.
Re-torque after the first 50 to 100 miles of driving and after temperature cycles.
TPMS: Transfer or install compatible sensors and perform relearn as specified by Cadillac. Follow the owner manual procedure or use a TPMS tool.
What is the bolt pattern for the 2018 Cadillac CTS?
5x120.
What center bore does the CTS use?
66.9 mm. If your new wheel bore is larger, use hub-centric rings sized 66.9 mm inner to your wheel’s outer bore.
Which OEM wheel and tire sizes are correct for my CTS?
The CTS was sold with multiple OEM packages. Data provided here includes a 19 x 8.5 ET34 wheel and, separately, a 245/45R17 tire size from another package. Check your driver door placard and owner manual, then validate in the wheelinterchange.com calculator.
Will 17 inch wheels fit my CTS?
The 245/45R17 size appears in OEM data for at least one package, but not all trims and brake packages will clear 17 inch wheels. Confirm caliper clearance physically and with the calculator before purchase.
What lug nuts do I need?
The thread is M14 x 1.5. The lug seat style must match your wheel. Verify whether your wheel requires conical, ball, or mag seats and use hardware designed for that seat type.
What offset should I choose for aftermarket wheels?
Use the known OEM ET34 on a 19 x 8.5 as your reference and compare your new offset in the calculator. Evaluate inner clearance to struts and outer clearance to fenders. Avoid large deviations without confirming clearance and handling effects.
Do I need wheel spacers?
Only if required for caliper or suspension clearance. Use hub-centric spacers with appropriate extended hardware and re-verify torque. Check that fender coverage remains legal in your area.
How do I keep the speedometer accurate when changing sizes?
Use the calculator to keep overall tire diameter close to your OEM package. Large differences can affect speedometer, ABS, and stability systems.
What is the correct torque for the lug nuts?
Do not guess. Consult your owner manual or OEM service information for the 2018 CTS and torque with a calibrated wrench. Re-torque after initial miles.
Will my TPMS sensors work with new wheels?
Yes if transferred or replaced with compatible sensors. Some sensors need programming or a relearn procedure. Follow Cadillac’s TPMS relearn steps or use a TPMS tool.
Methodology and sources
Wheel interchange depends on more than bolt pattern. Where data is available, this site compares recorded OEM values:
Bolt pattern / PCD
Center bore direction (donor wheel bore must not be smaller than the hub)
Wheel diameter, width, and offset against known OEM ranges
A normal wheel spacer does not change bolt pattern. Hub rings cannot enlarge a wheel bore that is smaller than the hub. Brake clearance and tire package fitment still require vehicle-specific checks when not confirmed in the dataset.
