What is in oil that gives it it's TBN?

[snoboy]

I understand its TBN that allows oil to stay in use and neutralize acid longer but I dont know what it is that makes up the Total-Base-Number.

 

[mdocod]

i would guess that the TBN is mostly related to the detergeny/antioxidant properties of the oil available and remaining. sulfer and magnesium being primary contributers.

this is my *guess*. hehe.

 

[TallPaul]

My guess is a number of adds provide TBN, including calcium and zinc. Also, I though I read that an ester base oil provides a TBN effect although not measured in the TBN test, which might explain why Redline TBN is not as high as some would expect. OTOH, maybe I don't know what I am talking about (except calcium--a no brainer TBN constituent).

Hey, I bet a search of the Question of the Day and/or Interesting Articles forums would answer the TBN question.

 

[Pablo]

Seems like you guys are on the right path, but you may want to search the "Question of the day" forum.

Basic (and di/tribasic) compounds (yes Ca, Mg) as well as amines (alkanolamines, etc) all provide acid nuetralizing properties (taking H+), therefore in a lab test will give a (higher) TBN....

But there is more to keeping an oil in use longer than a relatively high TBN.