Will rear axle out of 87 Yamaha 350 big bear work in 99 big bear?

The rear axle from a 1987 Yamaha 350 Big Bear is generally not compatible with a 1999 Big Bear due to differences in design, dimensions, and components. Yamaha typically made several updates and changes to their ATV models over the years. It's best to consult the service manuals for both models or seek advice from a Yamaha dealer or mechanic for accurate compatibility information.