1978 GMC G25 Wheels & Rims
Shop Wheels for 1978 GMC G25
The 1978 GMC G25 Rally, Rally STX, and Vandura models roll on a 5x127 bolt pattern with a stock setup of 15x6 wheels. Whether you're keeping it classic or stepping up in size, ThreePiece.us has verified fitment options ranging from 15 to 17 inches. Every wheel we offer is guaranteed to bolt on straight, and we ship free to the lower 48 states.
Finding the right wheels for your vintage GMC just got easier. We stock trusted brands like Black Rhino, Dirty Life, Carolina Forged, Fuel, Icon Alloys, Vision, 9Six9 Wheels, and LOCK OFFROAD in multiple sizes and styles to suit your build. All our wheels are tested for your specific fitment before they leave our warehouse, ensuring a perfect fit every time.
1978 GMC G25 Wheel Fitment Guide — What Works & What to Avoid
Your 1978 GMC G25 Rally, Rally STX, or Vandura requires a 5x127 bolt pattern. The factory wheel measures 15x6 with an 11-millimeter offset. You can step up to larger diameters—15x7, 15x7.5, 15x8, 16x6.5, 16x7, 16x7.5, 16x8, 17x7, or 17x7.5—all in square fitment. These options give you room to modernize your van's look while staying mechanically compatible.
Every wheel you mount must match the 5x127 bolt pattern; no other pattern will fit your hubs. The center bore sits at 77.8 millimeters, so use hub-centric rings if your chosen wheel has a larger bore to ensure proper centering. Aggressive offsets or very wide wheels risk contact with fenders and suspension components, so stay within the compatible size range listed above to avoid costly interference issues.
All wheels offered here are verified to bolt straight onto your G25 and ship free throughout the lower 48 states. In stock now are Black Rhino, Dirty Life, Carolina Forged, Fuel 1PC, Icon Alloys, Vision, 9Six9 Wheels, and LOCK OFFROAD—each ready to ship.
1978 GMC G25 Wheel Fitment Specifications
The 5x127 bolt pattern determines which wheels physically bolt onto your vehicle, while the 77.8mm center bore ensures a hub-centric fit. The factory equips this vehicle with 15x6 wheels at a +11 offset.
Lug Type
nut
Thread Size
1/2 UNF
Torque Spec
74 ft-lbs
TPMS
No
1978 GMC G25 Compatible Wheel Sizes
| Wheel Size | Offset Range | Compatible Tires | Notes |
|---|---|---|---|
| 15x6 | -19 to +15 | 225/75R15, J78-15, 235/75R15 | — |
| 16x6.5 | -19 to +15 | 225/75R16 | — |
| 15x7 | -19 to +15 | 205/75R15, 215/75R15, 30/9.50R15 | — |
| 16x7 | -19 to +15 | 205/80R16, 215/75R16, 215/85R16 | — |
| 17x7 | -19 to +15 | 215/70R17, 225/70R17, 225/75R17 | — |
| 15x7.5 | -19 to +15 | 215/75R15, 30/9.50R15, 205/75R15 | — |
| 16x7.5 | -19 to +15 | 205/80R16, 215/75R16, 215/85R16 | — |
| 17x7.5 | -19 to +15 | 215/70R17, 225/70R17, 225/75R17 | — |
| 18x7.5 | -19 to +15 | 225/60R18 | — |
| 15x8 | -19 to +15 | 215/75R15, 30/9.50R15, 205/75R15 | — |
| 16x8 | -19 to +15 | 205/80R16, 215/75R16, 215/85R16 | — |
| 17x8 | -19 to +15 | 215/70R17, 225/70R17, 225/75R17 | — |
| 18x8 | -19 to +15 | 225/60R18 | — |
| 19x8 | -19 to +15 | 235/55R19 | — |
| 20x8 | -19 to +15 | 235/55R20 | — |
| 20x8.5 | +null to +15 | 235/55R20 | 1. Check fitment, possible clearance issues |
| 20x9.5 | +null to +15 | 235/55R20 | 2. Body Modification Required |
Best Wheel Brands for the GMC G25
Complete Your 1978 GMC G25 Build
- GMC G25 suspension — pairs well with a wheel upgrade
- GMC G25 brakes — pairs well with a wheel upgrade
- Wheel & tire packages — pre-mounted, balanced, shipped ready to bolt on
- Installation accessories — hub rings, extended studs, TPMS kits, spacers