Dose anybody use an EP oil in the diff? I see no reason why a modern EP (extreme Pressure) oil souldn't be used. It is lighter viscosity and will do a better job. If the sorts of oil referred to above work, I think a 85 or 90 grade GL4 or GL5 would be more than OK.
Comments other than the usual "If Henry did it that way, I'll do it that way"? If EP oils were available to Henry, he'd have used them, I'm sure so why shouldn't we? I understand that the thicker oil in the gearbox makes changing down easier but there are no such considerations for the diff.
https://www.redlineoil.com/80w250-gl-5-gear-oil-2
80W250 GL-5 GEAR OIL
Recommended for SAE 250 or where SAE 140 does not provide adequate protection
Alternative to Red Line Heavy Shockproof® in problem Nitro Drag Race Vehicles
Can be used in Model A, Model T vehicles and Antique/Classic cars calling for 600W
Reduces noise levels in Morgan 3 Wheeler bevel boxes
Excellent for off road use where SAE 250 is required
API GL-5 is an engineering standard,API stands for american petroleum institute.SAE for society of automotive engineers.API GL-5 standard:
Gear Oil GL-5 delivers value through: ... The sulfur-phosphorus extreme pressure additive technology used in Gear Oil GL-5 provides good thermal and oxidation stability. In addition, this lubricant is fortified with rust and corrosion inhibitors, a foam inhibitor, and a pour point depressant.
Use a 250w in trans,85/90 GL-5 is fine for the rear axle.
Dose anybody use an EP oil in the diff? I see no reason why a modern EP (extreme Pressure) oil souldn't be used. It is lighter viscosity and will do a better job. If the sorts of oil referred to above work, I think a 85 or 90 grade GL4 or GL5 would be more than OK.
Comments other than the usual "If Henry did it that way, I'll do it that way"? If EP oils were available to Henry, he'd have used them, I'm sure so why shouldn't we? I understand that the thicker oil in the gearbox makes changing down easier but there are no such considerations for the diff.
https://www.redlineoil.com/80w250-gl-5-gear-oil-2
80W250 GL-5 GEAR OIL
Recommended for SAE 250 or where SAE 140 does not provide adequate protection
Alternative to Red Line Heavy Shockproof® in problem Nitro Drag Race Vehicles
Can be used in Model A, Model T vehicles and Antique/Classic cars calling for 600W
Reduces noise levels in Morgan 3 Wheeler bevel boxes
Excellent for off road use where SAE 250 is required
API GL-5 is an engineering standard,API stands for american petroleum institute.SAE for society of automotive engineers.API GL-5 standard:
Gear Oil GL-5 delivers value through: ... The sulfur-phosphorus extreme pressure additive technology used in Gear Oil GL-5 provides good thermal and oxidation stability. In addition, this lubricant is fortified with rust and corrosion inhibitors, a foam inhibitor, and a pour point depressant.
Use a 250w in trans,85/90 GL-5 is fine for the rear axle.