Wheels from Cadillac Escalade on Nissan Patrol: compatible?

No, the centre bore is too small

Same 6x139.7 PCD, but the centre bore of the wheels from Cadillac Escalade (78.1 mm) is smaller than the hub of Nissan Patrol (110 mm): they will not fit without being re-bored by a professional.

Cadillac Escalade1999–2006Nissan Patrol1987–1997
PCD6x139.76x139.7
Centre bore78.1 mm110 mm
Thread-Ecrous - 12x1.25
Original wheels R
R
≈8.5Jx18 ET28
≈8.5Jx20 ET27
R
≈7.5Jx16 ET10
≈8.5Jx18 ET35

≈: width estimated from the original tyre size.

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 Nissan Patrol (Ecrous - 12x1.25), 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 Nissan Patrol on Cadillac Escalade?