Yamaha BIG BEAR YFM400S Owner's Manual page 120

Final gear oil replacement
1. Remove the final gear case cover by re-
moving the bolts.
1. Final gear case cover 2. Bolt (× 2)
2. Place the machine on a level surface.
3. Place a container under the final gear
case to collect the used oil.
4. Remove the oil filler bolt and the drain
bolt to drain the oil.
1. Final gear oil drain bolt
5. Install the drain bolt, and then tighten it to
the specified torque.
Tightening torque:
Final gear oil drain bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
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