Just read this: http://machinerylubrication.com/Read/2170/oil-drain-interval-tan-tbn .
The graphic shows a study of 450 delivery trucks, and found that at some point before TBN falls to half of the original value, TAN starts to rise; and when the TBN hits the 1/3 (of the original amount) point, it starts to fall rapidly.
I don't seem to see much of a reaction (here by posters at BITOG, or by Blackstone itself) when Blackstone sends the UOA, and they simply want to see the TBN at at least 1.0. I realize there are different ways to determine the TBN, but I'm still thinking that either way, 1.0 is going to be pretty darn low.
So is concern about changing oil when TBN drops, a fools errand--or a solution looking for a problem? I mean, what is happening in the engine in the cars toward the right side of that graphic--and is it anything anyone needs to be concerned about? Does a TAN that is higher than the TBN mean that metal parts are literally getting eaten up? Or simply that if the oil isn't changed in another month or two, you might see this?
The graphic shows a study of 450 delivery trucks, and found that at some point before TBN falls to half of the original value, TAN starts to rise; and when the TBN hits the 1/3 (of the original amount) point, it starts to fall rapidly.
I don't seem to see much of a reaction (here by posters at BITOG, or by Blackstone itself) when Blackstone sends the UOA, and they simply want to see the TBN at at least 1.0. I realize there are different ways to determine the TBN, but I'm still thinking that either way, 1.0 is going to be pretty darn low.
So is concern about changing oil when TBN drops, a fools errand--or a solution looking for a problem? I mean, what is happening in the engine in the cars toward the right side of that graphic--and is it anything anyone needs to be concerned about? Does a TAN that is higher than the TBN mean that metal parts are literally getting eaten up? Or simply that if the oil isn't changed in another month or two, you might see this?
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