last time i changed the final drive oil on my tl140, i believe i used 75w-90 gl5 mobil synthetic. when i went to drain this time, the old oil came out dark and very frothy and aerated. not milky or anything like that. just lot of small air bubbles. the manual callls for sae 90 gl4 oil, which is hard to find. this time i put in valvoline 80w-90 gl5 gear oil. will that be ok? the one thing i read online is that the newer gl5 gear oils can cause wear on yellow metals like bronze or brass. do these final drives have yellow metal? i did see a lot of metal glitter in the old oil. machine has 600 hours.
I always use and recommend CAT TDTO 50, YMMV.
Use synthetic oil. I run Lucas 85w-140 in my SVL-95 Kubota.
what does kubota call for? seeing as how much glitter i saw in the oil, maybe i should go thicker.
Sorry for the delay, Kubota calls for 90w oil. Keep it changed, they take a beating on those things.