There are two TBN tests common to test labs, ASTM 2896 and ASTM 4739. ASTM 2896 will read about one unit higher than 4739. ASTM 4739 is often preferred for used oil, but labs can use either. The oil companies Data Sheet listings are almost always ASTM 2896. I learned this by talking to techs at WearCheck and ANA Labs. I can tell you:
WearCheck Uses ASTM 2896
ANA Labs Uses ASTM 4739
I have seen posted here that Blackstone uses ASTM 4739 but I have not confirmed that. If anyone can check and confirm Blackstone, and the other labs we use and post here, perhaps we can compile a list for a sticky so that we may be better able to compare TBN results.
WearCheck Uses ASTM 2896
ANA Labs Uses ASTM 4739
I have seen posted here that Blackstone uses ASTM 4739 but I have not confirmed that. If anyone can check and confirm Blackstone, and the other labs we use and post here, perhaps we can compile a list for a sticky so that we may be better able to compare TBN results.
Last edited: