Is there a specific weight oil used for this year?
Is it a worm drive?
At any rate: I had a visit from a Mobil tech rep yesterday: they still make 600 weight: ask for Mobil 600 weight Special Cylinder Oil. This may or may not apply to this specific application, but we do use 600 weight here and there.
RR
32 is not worm drive. Any decent quaility hypoid oil is fine, I prefer to run synthetic.