Manual says to use SAE 75w-90 or SAE 80w-90 gear oil
Yes, you can use 75w-90 gear oil instead of SAE 90 gear oil
SAE 80 or SAE 80w-90 below 50 f SAE 90 or SAE 80w-90 0 to 90 f SAE 140 above 50 f consistently
Sae 80w-90 gl-5
The cross reference for m-4864 which is a hydraulic oil or transmission fluid is SAE 80 for below freezing temperatures. B (SAE 90) is used for temperatures that are above freezing.
Do not use the oil instructed below.... 10w-30 is fine for mild climates. SAE 75W-90
SAE 80W-90 GL-5 gear lubricant, Full time 4x4 is SAE 10W30 or 40 engine oil.
The manual transmission uses SAE 80-90 weight gear oil.