By Mike Anderson, Senior Editor | September 28, 2010

A new "severe-duty" synthetic gear lube from Amsoil fills the gap between the 75W-90 and 75W-140 viscosity lubes that customers are accustomed to using. A blend of high viscosity, shear stable synthetic base oils and high-performance additives, Amsoil's new 75W-110 is designed to provide protection for elevated operating temperatures without sacrificing fuel efficiency. In the past, 75W-140 was used to obtain extra film protection beyond what the 75W-90 viscosity grade offered for differentials, but customers found they sacrificed fuel economy.