Removal (4.3L Astro & Safari)
WARNING: This page does not describe the selected car, but rather 55 other vehicles, including the 1999 Oldsmobile Bravada, 1999 GMC Yukon, 1999 GMC Suburban, 1999 GMC Sonoma, and 1999 GMC Sierra. However, it is still accessible from the selected car via links, so may be relevant.
Disconnect the negative battery cable. Raise and support vehicle. Drain crankcase and remove the oil filter. Disconnect oil cooler lines from pan and oil filter adapter. Remove oil filter adapter. Remove starter and flywheel shield. Disconnect transmission cooler lines. Remove front axle tube mount nuts and lower left drive axle bushing bolt (AWD). Remove rubber bellhousing plugs and remove oil pan bolts. Remove oil pan from vehicle.