Re: Mineral oil in transmission

Posted by Tim Cole On 2019/7/23 13:17:06

The present MIL spec for GL-5 gear oil requires non-reactivity with bronze. So modern gear oils are what is in most of those transmissions. The old Moss boxes specified motor oil due to bronze synchros the same way as Packard.

You can try a straight oil (available fro Lubriplate) and if the shift quality is poor change over to the GL-5 which is more grabby.