The 2007 Pontiac Grand Prix has a 5x115 bolt pattern, an OEM tire size of 255/45R18, and a 70.3mm center bore.

Other years of the Pontiac Grand Prix

2008 Grand Prix2006 Grand Prix2005 Grand Prix2004 Grand Prix2003 Grand Prix2002 Grand Prix2001 Grand Prix2000 Grand Prix1999 Grand Prix1998 Grand Prix1997 Grand Prix

2007 Pontiac Grand Prix Engine & Trim Levels

GXP
Bolt Pattern5x115
Center Bore70.3
Stud SizeM 12x1.5
Advertisement

Detailed tire and wheel breakdown for the 2007 Pontiac Grand Prix

Tire geometry — 255/45R18

The 255/45R18 fitted to the 2007 Pontiac Grand Prix has a section width of 255mm and an aspect ratio of 45%, mounted on a 18-inch rim. That gives a sidewall height of 114.8mm (4.52") and an overall outside diameter of 686.7mm (27.04"). At highway speed this tire completes roughly 464 revolutions per kilometre, which is what your speedometer and odometer are calibrated against.

Plus-sizing window

If you want to upsize wheels on the 2007 Pontiac Grand Prix while keeping the speedometer accurate, target a 265/39R19 (plus-one). For a softer ride or winter setup, a 245/52R17 (minus-one) keeps the overall diameter within Âą3% of stock, which is the industry tolerance for ABS and stability control to stay calibrated.

Wheel fitment specs

The 2007 Pontiac Grand Prix uses a 5x115 bolt pattern with a 70.3mm hub bore. Safe rim width range for the OEM tire is 7.5J – 8.5J, and offsets in the ET35 – ET45 window will clear suspension and fender without rubbing on most setups.

Staggered setup notes

The 2007 Pontiac Grand Prix ships staggered: 255/45R18 up front and 225/50R18 on the rear. That is a 225mm vs 255mm width difference — do not rotate front-to-rear, and replace tires in axle pairs to keep ABS and traction control balanced.

Tire pressure guidance

Manufacturer-recommended cold tire pressure for the 2007 Pontiac Grand Prix is printed on the driver-side door jamb sticker — always defer to that value, not to the maximum pressure printed on the tire sidewall. Check pressure monthly and before long trips; under-inflation by 20% can reduce tread life by 25%.

OEM Wheel & Tire Specs

Engine & TrimTire SizeRim SizeOffset (ET)
GXP
Rear: 225/50R18
18x8.0JET40

Frequently Asked Questions

What tire size does the 2007 Pontiac Grand Prix GXP use?

The 2007 Pontiac Grand Prix GXP uses 255/45R18 tires as standard equipment.

What is the bolt pattern of the 2007 Pontiac Grand Prix?

The 2007 Pontiac Grand Prix has a 5x115 bolt pattern with a center bore of 70.3mm.

What is the wheel offset of the 2007 Pontiac Grand Prix?

The 2007 Pontiac Grand Prix has a wheel offset of ET40.

Other Vehicles with 5x115 Bolt Pattern

The following vehicles share the same 5x115 bolt pattern as the 2007 Pontiac Grand Prix, making wheel interchangeability possible (verify offset and center bore before swapping).