Yeah. You can try a premium grade oil.

The cheaper ones i have had cause stiff shiftimg when cold in my 5spd. I put a more expensive brand into it and it improved it somewhat when cold. Even though it was still the same recommended viscosity oil.

But it might be a waste of good money if it isnt a miracle fix. I guess if it doesnt work you could drain and collect the fresh oil for later. Then shell out for an expensive rebuild.

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Doing it for all the wagons out there