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Gentlemen: I have a question on what type of gear oil to use in the T-84 Tranny and front and rear axles on a Willys MB. Is it Straight 90 Weight Gear Oil in all three?

I seem to recall Wes warning against using Hypoid gear oil in Jeep transmissions because it can effect certain alloy transmission parts.

Thanks, Dennis V.

It really boild down to the climate in which you operate your MB. Straight weights are fine.
Only important issue is to avoid any Hi-Sulpher content gear oils in your tranny. The modern multi's have hi-sulpher but a few state they are ok to use with non-ferrous tranny parts like synchro rings.

You can use the Hypoid gear oils in the axles and use plain gear oil in the tranny.

Thanks Wes.