Hello, I am looking to change the differential oil in a 76J 966C Cat Loader the book reference is 90w oil. However, i am finding this hard to find. Have the oil recommendations changed since then or do I need to find this specific oil. Thanks
You're correct, specs have changed over the years and Cat have gone away from EP oils in diffs & final drives. Use an SAE50 TO-4. It will work fine. Because the two types of oil are classified differently the viscosity of an SAE50 TO-4 is actually pretty much the same as an SAE90 EP oil.
What I find strange is the listing for brake fluid down at the bottom of the page. Been a few years since I actively worked on a 76J Cat but every one we had had straight air brakes, not air over hydraulics. Then again this might be a "generic" type fluids chart and not one specific to the 966C family.
Perfect thanks guys!
It's been a while but I think the 966 shared an operators manual with both a 950 and a 980 so somewhat generic.