It probably be tuff torq there is normally a sticker on rear of axle with code telling what model it is k46 is common one also get k55 k61 etc.from this model number tuff torq website has details of oil type and level for your model. Oil can be changed, tricky to do as no sump plug,it has to be siphoned out or axle removed.hope this helps
Rab, May 2020