Ok thanks for the explanation I have ordered the miller classic oil for the rear. It’s hypoid rated and yellow metal safe so should be good to go.
Now im going to stick with the above two types of oil for transmission and rear better to be sure etc But looking at the term straight mineral oils shall not be used in the rear. Now both oils are minerals oils as would be most hypoid oils excluding the modern synthetics. So I’m guessing the use of mineral oils is fine in the transmission and rear. So it comes back to the word “Straight” My understandings of the word straight is it means a pure mineral oil without additives. Now going back to the two oils I listed both are mineral oils and neither of them are straight mineral oils as they have extreme pressure additives. I suspect both oils could be the same thing. Anyway just thought this was interesting if there are any oil experts reading this. I could be totally wrong but it would be nice to know either way.
I guess back in the day there were just less types of oil around and you probably had straight mineral oils and then everything else under the multipurpose label. It must be a common question as multipurpose oils don’t exist as a specification
Thanks for the advices. Best regards Chris
Last edited by ThreeSixHundred; 02/27/2019 6:42 AM.
