FJ40Savvy
SILVER Star
When I search which oil to use for the transfer case most of the threads are 7-10 years old. I have searched in my area and the only gear oil I can find is blends i.e. 80w90 GL-5 etc. The FSM says SAE90 GL-4. In some of the old threads, there are comments that only GL-4 should be used in older transmission and transfer cases. I have a stock 1973 3 Speed with pto. Any guidance would be appreciated.