Can low quality fuel affect oil?

[NICAT]

Hi.
This is what any engine expert tells in my country:
"Our fuel is very low in quality, so it degrades the oil faster. (May be like unburnt fuel mixes with oil) And we should change oil in 5k mile instead of 7.5-10k mile"

Can really fuel quality affect oil even if it doesn't affect engine's smoothness?

 

[SuperSalad]

I'm not sure of the fuel quality in Azerbaijan, but if it is low quality fuel, meaning it is impure and does not contain proper levels of detergents and other additives, that would certainly affect the oil. Oil degradation is strongly affected by contaminants and a lot of those of those come from the fuel.

 

[Pelican]

Originally Posted by NICAT
Hi.
This is what any engine expert tells in my country:
"Our fuel is very low in quality, so it degrades the oil faster. (May be like unburnt fuel mixes with oil) And we should change oil in 5k mile instead of 7.5-10k mile"
Can really fuel quality affect oil even if it doesn't affect engine's smoothness?


+1 on what MotoTribologist said and I'd add to change the fuel filter at least twice as often as recommended.

 

[camrydriver111]

High sulfur fuels can deplete TBN faster.

 

[The_Jeff]

^ Yup that and if it's bad enough to misfire that'll trash the oil too.