While I don't agree with 25,000 mile oil changes without a seriously good oil filtration system, It's not all about the TBN it's about the rest of the wear particles, TAN, and for diesels soot levels. Vehicles in the Philippines are not using ULSD like in the US. So the testing somewhat does not apply. And not only is it not ULSD it's not exactly the cleanest diesel in the world either and tends to foul your oil quicker than it would state side.

Most of this stuff has been covered on anouther thread but this good information you have posted. knowone should blindly run thier oils for over 12000miles/20000kms especially in the Philippines, Remember many people are still using VIC oil filters and other low quality oil fitlers that have nowhere near the efficiency of oil filters found in the US.

And with the number of older diesels with mechanical diesel injection it's really not advisable they are not exaclty efficient when it comes to burning all there diesel and make a lot of soot and carbon. You should only base your oil change intervals off of base line facts then include in the variables as I have pointed out. There are actaully a bunch more but I don't feel like beating a dead horse on this issue.

Every vehicle is different just like the enviorment they operate in and the driving conditions they encounter on a daily basis. A engine oil analysis is key. For instance I can assure you that you will have a much higher silicon count in Metro Manila than most cities in the US due to the pollution (another one of those factors I am talking about).

Once people start to do oil testing and posting some results then Tsikot members will have a true base line to go off of for oil change intervals for there vehicles. But for now 10000km to 12000km is a very safe level when using a quality oil filter, 15000kms is really not pushing it to hard with a Fleetguard or Baldwin filter either. But a VIC no way, your going to have seriours wear count numbers.

Again very good information you have posted. But definetly not applicable to all vehicles in all enviorments in all situations. To many factors are out there.