GM08

RTX GM08: Monoblock 6x139.7 Truck Wheel

The RTX GM08 is a monoblock wheel built for six-lug trucks and SUVs running the 6x139.7 bolt pattern. Its single-piece construction and clean, aggressive spoke face suit half-ton pickups and body-on-frame SUVs that want a purposeful street-and-trail look without going overboard. It sits within the wider RTX lineup, where each model targets a different fitment and style.

Sizes and fitments stocked

The GM08 is focused, so the specs are easy to pin down. Every size we carry runs a 9-inch width, a +20 offset and the 6x139.7 bolt pattern, in three diameters:

  • 17x9 +20 — the compact, trail-friendly choice for taller sidewalls.
  • 18x9 +20 — the middle-ground fit that balances stance and ride.
  • 20x9 +20 — the largest diameter for a bolder, filled-out look.

The +20 offset keeps the face tucked without poking heavily, and the 9-inch width works on the 6x139.7 platforms common to popular half-ton trucks and SUVs. Run the numbers against your vehicle on the fitment calculator before you order.

Finish

The GM08 comes in Gloss Black, a deep, easy-to-maintain finish that pairs with just about any factory paint. If you want to see other RTX tones, browse Black RTX wheels, Gray RTX wheels or Silver RTX wheels.

Price and who it suits

The GM08 runs from about $242 for the 17x9 up to $342 for the 20x9, per wheel. That makes it a sensible pick for truck and SUV owners who want a solid monoblock wheel with a modern face at a fair price. Financing is available through Affirm, Katapult, Klarna, PayPal Credit and Snap Finance at checkout — see financing for details.

Other RTX models to weigh

If the GM08 isn't quite the look you're after, the Stag brings a different truck-oriented spoke pattern, while the Trek leans rugged for off-road builds. The Spark and Crush aim at a sportier, car-focused audience, and the Force offers another aggressive face to compare.

ThreePiece.us is an authorized dealer selling 100% genuine wheels, with free shipping on all orders and 30-day returns on unmounted wheels. Need help confirming the GM08 works on your truck? Call our fitment team at 813-535-5801 or reach out through contact us.

RTX GM08: Monoblock 6x139.7 Truck Wheel

The RTX GM08 is a monoblock wheel built for six-lug trucks and SUVs running the 6x139.7 bolt pattern. Its single-piece construction and clean, aggressive spoke face suit half-ton pickups and body-on-frame SUVs that want a purposeful street-and-trail look without going overboard. It sits within the wider RTX lineup, where each model targets a different fitment and style.

Sizes and fitments stocked

The GM08 is focused, so the specs are easy to pin down. Every size we carry runs a 9-inch width, a +20 offset and the 6x139.7 bolt pattern, in three diameters:

  • 17x9 +20 — the compact, trail-friendly choice for taller sidewalls.
  • 18x9 +20 — the middle-ground fit that balances stance and ride.
  • 20x9 +20 — the largest diameter for a bolder, filled-out look.

The +20 offset keeps the face tucked without poking heavily, and the 9-inch width works on the 6x139.7 platforms common to popular half-ton trucks and SUVs. Run the numbers against your vehicle on the fitment calculator before you order.

Finish

The GM08 comes in Gloss Black, a deep, easy-to-maintain finish that pairs with just about any factory paint. If you want to see other RTX tones, browse Black RTX wheels, Gray RTX wheels or Silver RTX wheels.

Price and who it suits

The GM08 runs from about $242 for the 17x9 up to $342 for the 20x9, per wheel. That makes it a sensible pick for truck and SUV owners who want a solid monoblock wheel with a modern face at a fair price. Financing is available through Affirm, Katapult, Klarna, PayPal Credit and Snap Finance at checkout — see financing for details.

Other RTX models to weigh

If the GM08 isn't quite the look you're after, the Stag brings a different truck-oriented spoke pattern, while the Trek leans rugged for off-road builds. The Spark and Crush aim at a sportier, car-focused audience, and the Force offers another aggressive face to compare.

ThreePiece.us is an authorized dealer selling 100% genuine wheels, with free shipping on all orders and 30-day returns on unmounted wheels. Need help confirming the GM08 works on your truck? Call our fitment team at 813-535-5801 or reach out through contact us.