FRENES

Wheels from Cadillac Seville on Pontiac Grand Am: compatible?

Yes, with hub centric rings

Same 5x120.65 PCD, but the centre bore of the wheels from Cadillac Seville (78.1 mm) is larger than the hub of Pontiac Grand Am (70.3 mm): you need 4 hub centric rings 78.1 → 70.3.

Rings 78.1 → 70.3

Cadillac Seville1975–1979Pontiac Grand Am1964–1980
PCD5x127 / 5x120.65 / 5x1155x120.65 / 5x100 / 5x115
Centre bore78.1 mm70.3 mm
ThreadEcrous - 1/2 - 20 UNEcrous - 7/16 - 20 U
Original wheels ≈6.5Jx14 ET43
≈6.5Jx15 ET10
≈7Jx16 ET51
≈7.5Jx16 ET51		 ≈6.5Jx13 ET42
≈6Jx14 ET41
≈7Jx15 ET8
≈7Jx15 ET42

≈: width estimated from the original tyre size.

Wheel by wheel: offset and tyres

Each original wheel from Cadillac Seville is compared with the one from Pontiac Grand Am of the same diameter: how much closer the wheel gets to the shock absorber or how far it sticks out of the wheel arch, and whether the tyre keeps the same overall diameter.

  • ≈6.5Jx14 ET43 · 205/75R14 — Check on the car

    Compared with the original ≈6Jx14 ET41 on Pontiac Grand Am: shock absorber side +8.4 mm, wheel arch side +4.4 mm, tyre diameter +4.7 % : fit it with the original tyre size of Pontiac Grand Am (185/75R14), not that of Cadillac Seville. Comparison for guidance only (estimated width). Check in detail

  • ≈6.5Jx15 ET10 · 205/75R15 — Fits like the original

    Compared with the original ≈7Jx15 ET8 on Pontiac Grand Am: shock absorber side −4.3 mm, wheel arch side −8.3 mm, tyre diameter −1.1 %. Comparison for guidance only (estimated width). Check in detail

  • ≈7Jx16 ET51 · 225/60R16

    Pontiac Grand Am has no 16-inch original wheel in our data: check the approved fitments and caliper clearance.

  • ≈7.5Jx16 ET51 · 235/60R16

    Pontiac Grand Am has no 16-inch original wheel in our data: check the approved fitments and caliper clearance.

Before fitting the wheels

An identical hub is not enough: offset, width and diameter change the position of the wheel, and larger calipers can touch a smaller wheel. Original wheels often use bolts or nuts with a specific seat: keep the fixings intended for the wheel, with the thread of Pontiac Grand Am (Ecrous - 7/16 - 20 U), tightened to the torque shown on its vehicle page. Finally, check that the size is among the approved fitments for your vehicle. This comparison is for guidance only: have the fitting approved by a professional.

And the other way round: wheels from Pontiac Grand Am on Cadillac Seville?