Hi all, I am looking to change the engine oil in my 1959 Mack B61 with a 711 thermodyne in it. I am not a mechanic by trade and cannot afford to take it to a shop (I bought it so I could learn by doing anyhow). I have done plenty of oil changes on my day to day vehicles but realize this is a different machine. I haven’t located any service books for my model (at least none that I could afford) so my hope is that someone here would be willing to let me know: what viscosity I need, gallon quantity, and suggested brand of oil. I also need to know what oil filter I would need. My father is a heavy machine mechanic so do not worry about me destroying anything or hurting myself. He is willing to help me if I ask. Unfortunately we are both stumped on these details at the moment.
Thank you for reading.