Mobil1 users
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Mobil1 users
I was looking at the Mobil1 specs and found out that the 5W30 and 10W30 viscosities do not meet ACEA A3/B3 specifications. What does this mean?
It means that these oils do not reach a HTHS value of 3,5 or higher.
High-Temperature/High-Shear
This test is a simulation of the shearing effects that would occur within an engine. In fact, it's actually designed to simulate motor oil viscosity in operating crankshaft bearings.
Under high stress conditions where shearing can occur, the VI Improvers (polymers) break down. As they do, the viscosity of the oil decreases. This is what the High Temperature/High Shear test checks for.
The HT/HS test is measured in Centipoise (cP) as the Cold Crank Simulator test is. However, in this case, because you're hoping for the least loss of viscosity with an increase in heat and stress, you want the cP value to remain high.
Do not forget to look at the VI, HTHS, API, ACEA, TBN specifications before buying an engine oil.
It means that these oils do not reach a HTHS value of 3,5 or higher.
High-Temperature/High-Shear
This test is a simulation of the shearing effects that would occur within an engine. In fact, it's actually designed to simulate motor oil viscosity in operating crankshaft bearings.
Under high stress conditions where shearing can occur, the VI Improvers (polymers) break down. As they do, the viscosity of the oil decreases. This is what the High Temperature/High Shear test checks for.
The HT/HS test is measured in Centipoise (cP) as the Cold Crank Simulator test is. However, in this case, because you're hoping for the least loss of viscosity with an increase in heat and stress, you want the cP value to remain high.
Do not forget to look at the VI, HTHS, API, ACEA, TBN specifications before buying an engine oil.