Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "Are They All The Same Motor Oil? Let's Settle This! Four Levels of Pennzoil Motor Oil Compared" video.

Interesting tests! Could you do a similar test for some oils designed for diesel engines? There fuel contamination is even more common especially when the engine is cold but as diesel fuel is not a solvent in itself, I would assume the results are less serious. It would be great to see practical tests about that, though! Also, cranking a diesel engine in cold conditions is very hard for the battery and any little improvement you can get from the oil in cold cranking helps to get the engine running. I live in Finland where it's not uncommon to see days with -30 °C during the winter and we have to drive cars in those days, too.
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