There is usually a tag on the axel with the info you need. If all else fails call your local GM dealer or 4x4 shop.
75w90 gear oil.
80W90 gear oil.
90 weight gear oil
gear oil
What type of rear axle fluid is used in a 2006 GMC 5500
Use 80-90 gear oil.
SAE 75W90 synthetic gear oil.
Hypoid gear oil 80w90
80W90 SAE MOPAR 4874468
If you are asking about the rear differential, It is - SAE 75W90 synthetic gear oil The front is -SAE 80W90 GL-5 gear oil
you will need to use 80 90 weight greese in that
Depends on which you have and what you use the Truck for. Standard Differential, Rear Dana 135.....GL-5[3] All Temps......75W-140 Amsoil Severe Gear 75W-140 or SAE 80W-140 Synthetic Gear Lube Controlled Slip Differential, Rear Dana 135.....GL-5*[3][4] All Temps......75W-140 Amsoil Severe Gear 75W-140 Controlled Slip Differential, Rear Dana 80.....GL-5*[5][6] All Temps......75W-90 Amsoil Severe Gear 75W-90 Standard Differential, Rear Dana 80.....GL-5[7] All Temps......75W-90 Amsoil Severe Gear 75W-90, SAE 75W-90 Synthetic Gear Lube or Severe Gear 75W-110 These recommendations are for a 2004 F350. Standard Differential, Rear Ford.....GL-5[7] All Temps......75W-140 Amsoil Severe Gear 75W-140 or SAE 80W-140 Synthetic Gear Lube Controlled Slip Differential, Rear Ford.....GL-5*[7][8] All Temps......75W-140 Amsoil Severe Gear 75W-140 Standard Differential, Rear S110, S130.....GL-5[9] All Temps......75W-140 Amsoil Severe Gear 75W-140 or SAE 80W-140 Synthetic Gear Lube