Consult your owner's manual for the exact location. It should have a diagram showing the recommended jacking points. If you don't have the manual, you can often find a PDF version online by searching "[Year] Pontiac Montana owner's manual."
Failing that, visually inspect the frame rails near the front wheels. You'll likely find a slightly reinforced or thicker section of metal designed for jacking. Use a jack stand for safety once the vehicle is raised even slightly. Never work under a vehicle supported only by a jack.
