Mixing brands with same weight

tradosaurus

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After searching around town I guess I found the last container of 5W-40 diesel oil. I used Valvoline Premium Blue Extreme.

Also ordered 3 gallons of the same from Amazon but will have to wait a month for delivery.
 
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I never saw any significant difference in UOA results when we changed from Delo, Delvac and Rotella through the years (Which resulted in a different bramd of add oil being used). After 40,000 mi a lot of trucks had a significant percentage of add oil.
 
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Keep in mind, every time you change the oil you leave roughly 5-15% or about 1/2 to 1 full quart of old (often unknown) oil in the crank, pan (and filter if you don't also change filter). By virtue of math, that old oil is a small percentage of oils from many oil changes ago.

You are almost certainly "mixing" oils of various brands and sometimes even weights (unless you know for certain the exact same brand/weight and formula has always been used).

Yeah, it's generally going to be fine b/c makers know oils get mixed routinely.
 
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I never saw any significant difference in UOA results when we changed from Delo, Delvac and Rotella through the years (Which resulted in a different bramd of add oil being used). After 40,000 mi a lot of trucks had a significant percentage of add oil.
It wouldn’t be expected that you would.
 
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