Oil Viscosity

[ice15]

Do Thin Oils Destroy Engines? Lessons From GM’s Massive Recall
Engineering Explained

[dr. d]

Do Thin Oils Destroy Engines? Lessons From GM’s Massive Recall
Engineering Explained

from what i understand,
the engine failure was attributed out-of-spec components and/or sub-optimal assembly.
but they found that using a heavier oil somehow... mitigated the problem.
so between the expensive solution of quality parts manufacture and assembly, and simply using heavier oil...

it's like seiko.
instead of going thru pains in adjusting their more popular movements,
they simply "lower the written standard of accuracy in their brochures".
smart.
in my opinion.
heh heh.

[ice15]

growing up in the PUV business.

both mechanics namin before strongly believes that you should use thicker oil on older engines...

it felt really strange when I read about GM's solution to their engine problems...

[dr. d]

growing up in the PUV business.

both mechanics namin before strongly believes that you should use thicker oil on older engines...

it felt really strange when I read about GM's solution to their engine problems...

kasi,
heavier oils tend to result in higher engine oil pressures, to compensate for the looser tolerances "inherent in worn engines".
whether this helps stave off engine failure or not, i do not know. whether it tends to "tighten spaces between loose metal surfaces", i do not know.
but i do know that using heavier oil can tend to "silence" oil pressure gauge warnings... something bayan sellers take advantage of.

some years back,
i read that modern engines have smaller oil passages and tighter tolerances than older engines.
thus, the need for lighter oils, so that they can more easily pass thru these smaller-caliber oil passageways.

[oj88]

All else being equal, a relatively higher viscosity oil is better for engine longevity. The main reason why low-viscosity oil is being pushed is for fuel economy.

[Dr.Kamiya]

kasi,
heavier oils tend to result in higher engine oil pressures, to compensate for the looser tolerances "inherent in worn engines".
whether this helps stave off engine failure or not, i do not know. whether it tends to "tighten spaces between loose metal surfaces", i do not know.
but i do know that using heavier oil can tend to "silence" oil pressure gauge warnings... something bayan sellers take advantage of.

some years back,
i read that modern engines have smaller oil passages and tighter tolerances than older engines.
thus, the need for lighter oils, so that they can more easily pass thru these smaller-caliber oil passageways.

I think scientifically proven that heavy oils give more protection talaga. And even on modern engines with small passages the heavy oil can still flow through.
The disadvantage is reduced power and efficiency, but if the engine often run hot (either hataw, traffic, or plain hot environment) using a heavier oil will be an advantage.

[EJR_IS350]

I strongly advise that you follow the factory recommendations for your vehicle’s oil viscosity. Check your owner’s manual for details.