You can get some spray adhesive at your local auto parts store and try to reglue it. But your best bet is to take your truck to a trim shop and have a new headliner installed. Cost should be around $100.
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'97 2500 4X4 club cab, BLACK, Leer XL-100,running boards , cup smoothie, EZ Drain, 103,000 miles
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'97 2500 4X4 club cab, BLACK, Leer XL-100,running boards , cup smoothie, EZ Drain, 103,000 miles