RK 55HC,ym1700, NH7610S, Ford 8N, 2N, NAA, 660, 850 x2, 541, 950, 941D, 951, 2000, 3000, 4000, 4600, 5000, 740, IH 'C' 'H', CUB, John Deere 'B', allis 'G', case VAC
I put 15w40 motorcraft hd diesel oil in my 5000 and 7610s.. in my 3000 I go with walmart 15w40 ( and most of my gassers are now running that 15w40 walmart oil too ).
in my 7.3psd I run valvoline blue premium synthetic.
for what it's worth.. or regular changes the walmart oil is likely not close to being worn out, vs the higher dollar motorcraft oil.. etc.
Delo 400 or shell rotela in all of my diesels. No problems with ether. Both rated CD and work well. I use both multi an single weight depending on the engine.
Read the owners manual. Or as we used to say in the networking biz that I spent 30+ years, RTFM.
Amsoil Formula 4-Stroke® 10W-30/SAE 30
Synthetic Small Engine Oil (ASE)
Commercial-Grade Synthetic Oil for
Compact Gasoline and Diesel Engines Operating
Under Adverse Conditions