1918 E49 Buick Info Needed

[Doug Ruth]

Simple question- what grade of lube for the rear end differential gears and what quantity for our 1918 Buick? None of my literature addresses this.

[Akstraw]

My 1915 Dyke's manual says "two parts grease, one part oil".    My 1915 Buick owners manual calls for "steam cylinder oil", while the 1917 Questions and Answers on Automobile Design Construction and Repair recommends [steam] cylinder oil or a mixture of [steam] cylinder oil and engine oil.  More helpful, perhaps, is the advice of Harold Sharon in Understanding Your Brass Car:  "Modern 90/140EP rear end lubricant works well."

Edited December 31, 2022 by Akstraw
added more info (see edit history)

[Mark Shaw]

SAE 250 or equivalent.  Most rear ends have a bottom drain and a fill plug at the half full. 

If you use lighter weight lube, it will often leak out onto the rear brakes.

Viscosity Charts - Bob is the Oil Guy

 

Edited December 31, 2022 by Mark Shaw (see edit history)

[Larry Schramm]

This is what I use.  You might want to read the material specifications.

 

https://www.lubriplate.com/Products/Fluid/SPO-Series/SPO-299/SPO-299