I had my Hyundai Excel's gear box filled with this oil:
CALTEX GL-5 SAE-90 THUBAN. I bought the original box from Caltex petrol station in Islamabad Super Market. On the box, it reads meets GL-4 requirements. The oil is a tad thick/slightly heavy but the transmission is smooth and there are no grinding issues.
@onlyfaith My pleasure bro.