GMC Sierra 1500 Bolt Pattern, Wheel & Tire Sizes

Quick answer: Every GMC Sierra 1500 generation from 1999 to today (GMT800, GMT900, K2XX and T1XX) uses the same 6x139.7 mm (6x5.5 in) bolt pattern with a 78.1 mm centre bore and M14x1.5 wheel studs, though wheel and tire sizes grow substantially from the 16-17 inch wheels of early trucks to the 20-22 inch options on newer AT4 and Denali models.

TL;DR

The Sierra 1500 has kept the same 6x139.7 (6x5.5) bolt pattern and 78.1 mm centre bore since 1999, so wheels swap between generations, but stock rim and tire sizes vary a lot by trim and year.

Bolt pattern has stayed consistent since 1999

Unlike some SUVs that change bolt pattern across generations, the full-size GMC Sierra 1500 has used 6x139.7 mm (6x5.5 in) continuously from the 1999-2006 GMT800 generation through the current T1XX-based trucks. This was confirmed on wheel-size.com listings for the 1999-2006, 2007-2013, 2014-2018 and 2019-2023 ranges, all showing the same pattern with a 78.1 mm centre bore and M14x1.5 stud thread.

What changes between generations

What does change substantially is the factory wheel diameter and tire size offered per trim. Early 2000s base trucks commonly rode on 16-17 inch steel wheels, while modern SLT, AT4 and Denali trims are offered with 20 inch and larger wheels from the factory. Diesel and higher payload configurations often get different (frequently taller sidewall, LT-rated) tires than gas half-ton trims, even within the same model year.

Centre bore and hub rings

The 78.1 mm centre bore figure is well corroborated across the 1999-2018 trucks. For 2019-and-newer T1XX-generation Sierras, some fitment databases list a narrow 77.8-78.1 mm range depending on the specific listing, so if you are fitting aftermarket wheels with a different bore, use hub-centric rings rather than assuming a bare number.

Always confirm on your own truck

Because wheel and tire choice varies by trim, engine and even by regional market, do not rely solely on a generation-wide table. Before buying wheels or tires, check:

  • The driver-side door jamb placard, which lists the factory tire size and cold inflation pressure for your exact build
  • The owner's manual tire and loading information section
  • The size markings molded into the sidewall of your current tires
  • GM's/GMC's towing and capacities guide if you plan to change wheel or tire diameter, since it can affect speedometer calibration and payload rating

Specifications by generation

Generation / yearsBolt patternCentre boreStud threadStock wheel sizesCommon tire sizes
GMT800 (1999-2006)6x139.7 (6x5.5)78.1 mmM14 x 1.516-17 in steel/alloy245/75R16, 265/70R17 (varies by trim)
GMT900 (2007-2013)6x139.7 (6x5.5)78.1 mmM14 x 1.517-20 in alloy245/70R17, 265/65R18, 275/55R20
K2XX (2014-2018)6x139.7 (6x5.5)77.8-78.1 mmM14 x 1.517-20 in alloyLT245/75R17, LT265/70R17, LT265/65R18, LT275/55R20
T1XX (2019-present)6x139.7 (6x5.5)77.8-78.1 mmM14 x 1.517-22 in alloy255/70R17, 265/65R18, 275/60R20 (AT4/Denali trims vary)

Summary

Bolt pattern (all generations, 1999-present)6x139.7 mm (6x5.5 in)
Centre bore, 1999-201878.1 mm
Centre bore, 2019-present77.8-78.1 mm (sources vary slightly)
Stud threadM14 x 1.5
Stock wheel size range16 in to 22 in depending on trim/year
Common tire sizes245/75R16 up to 275/60R20, trim dependent
Authoritative source for your exact truckDriver door jamb placard and owner's manual

Full diagnostics

For the complete step-by-step diagnostic and repair guide, see GMC Sierra 1500: Common Problems, Fault Codes & Repairs.

Frequently asked questions

Do wheels from an older Sierra 1500 fit a newer one?

In terms of bolt pattern, yes: every generation from 1999 onward uses 6x139.7 (6x5.5) with a 78.1 mm centre bore and M14x1.5 studs, so the wheels will physically bolt on. However, offset, wheel diameter and load rating differ by trim and year, so check that the specific wheel's offset and load rating match your truck before installing it.

What is the factory lug nut torque for a Sierra 1500?

We could not verify a single torque figure that applies across all Sierra 1500 generations and trims from a corroborated source, and GM has changed stud/nut specifications over the years. Look up the torque value in your owner's manual or a generation-specific factory service manual rather than relying on a generic number.

Why do two trucks of the same model year have different tire sizes?

GMC offers different wheel and tire packages depending on trim (base, SLE, SLT, AT4, Denali), cab/bed configuration, and engine, since these affect load capacity and ride height. The only way to know your exact factory size is to check your door jamb placard or the sidewall markings on your current tires.

Is the centre bore the same on all Sierra 1500 wheels?

Multiple listings agree on 78.1 mm for 1999-2018 trucks. For 2019-and-newer T1XX trucks, some databases show a slightly narrower 77.8-78.1 mm range across listings, likely reflecting rounding differences between sources rather than a real running change. If you are installing an aftermarket wheel with a different bore diameter, use a hub-centric ring to take up the gap safely.

Where the binding figure is on your car

The figures on this page are per-generation references compiled from manufacturer documentation and established fitment databases. Where your own vehicle disagrees with them, your vehicle is right.