Will a 4.8 liter vortec motor from a 2001 Chevy silverado 1500 fit into a 1999 gmc sierra 1500 with a 4.8l?

Yes, a 4.8-liter Vortec motor from a 2001 Chevy Silverado 1500 can fit into a 1999 GMC Sierra 1500 with a 4.8L engine. Both trucks share similar engine mounts and transmission configurations, making the swap relatively straightforward. However, you may need to address differences in wiring harnesses and engine control modules between the two model years. Always verify compatibility with specific components to ensure a successful installation.