Cat D4D SA oils

I know this topic has been gone over a lot! But looking in my service manual the callout for d4d direct drive oil is sae30, I have Phillips 66 powerdrive 30 and that is the new T0-4 oil. I been running 80w-90 in the finals but want to switch to powerdrive 50. I do run it in the winter pushing snow, so should i run powerdrive 30 in trans or the 50? Also what oil for the clutch? Just stay with 30? Any help would be appreciated thanks!

Yes Cat at time was going But changed with the TO oil in the finals as well as transmission. Even suggesting that in older equipment. But changed their mind after a few years. So I would say for warm/hot weather the heavier oil in final's might be better. In your case talking of pushing snow, the lighter would seem better to me. But I am just a farmer, that ran whatever was cheap equipment over time.

We have 50w in our clutch, operating in warm weather and it can drag a little until the oil is warmed up. I would think 30w would be better for you in the snow. For the finals I would want the most protection possible so I would think 50w or 80w-90 like you have would be fine too.