1989 Jeep Wrangler transmission fluid change?

Remove transmission pan. Fluid will drain out. Buy a new transmission filter. Usually held on by 2 screws or bolts. New gasket pan gasket should come with filter. Install new filter and pan gasket fill with fluid through dip stick opening. Do not overfill. Most transmissions take about 5 quarts. Check with auto parts store to get correct type.They should be able to tell you how many quarts your car requires. Add about 3 to 4 quarts Depending on size of transmission,start engine check fluid level while engine is running (should let it warm up) Add fluid as needed to fill to full line. Do not overfill!!!