1999 GMC Sonoma Owner's Manual - Page 357

yellowblue USAGE Chassis Lubrication FLUID/LUBRICANT Chassis Lubricant (GM Part No. 12377985 or equivalent) or lubricant meeting requirements of NLGI # 2, Category LB or GC-LB. Wheel Bearing Lubricant meeting requirements of NLGI # 2, Category GC or GC-LB (GM Part No. 1051344 or equivalent). SAE 80W-90 Axle Lubricant (GM Part No. 1052271 or equivalent). SAE 80W-90 Axle Lubricant; use only GM Part No. 1052271. Do not add friction modifier. Automatic Transfer Case Fluid (GM Part No. 12378396). USAGE Rear Driveline Center Spline and Universal Joints Constant Velocity Universal Joint FLUID/LUBRICANT Chassis Lubricant (GM Part No. 12377985 or equivalent) or lubricant meeting requirements of NLGI # 2, Category LB or GC-LB. Chassis Lubricant (GM Part No. 12377985 or equivalent) or lubricant meeting requirements of NLGI # 2, Category LB or GC-LB. Chassis Lubricant (GM Part No. 12377985 or equivalent) or lubricant meeting requirements of NLGI # 2, Category LB or GC-LB. Front Wheel Bearings Front and Rear Axle (Standard Differential) Rear Axle (Locking Differential) Automatic Transfer Case Clutch Pushrod to Clutch Fork Joint 7-49