Hi,
at least this discussion has shown some healthy viewpoints and raised all of our knowledge levels
Terry - I agree that both TBN and TAN results are desirable. I suppose you can get what you are prepared to pay for - even if the recipient may not fully understand the results. For the average user on here the TBN result is the best known - even both of them! But even the change from one to another TBN determination alone caused a bit of shock reaction here
ExxonMobil are not stupid and their move to TAN alone was probably a well balanced commercial and certainly a sincere technical decision. Their Engineers confirm this
Regarding fuel - Australia had high sulphur levels until about three years ago. At present they are now the same as in NA. Our heavy diesels use the Euro 3 & Californian emission standards. Our cars are also subject to emission legislation based on both Euro and NA standards
From my viewpoint please note the following examples in the use of TAN & TBN ( all Delvac 1 5w-40 - TBN to D4739):
Example 1
Truck A
At 9/5/00 - Engine at 126kkms ( average oil temp 103C )
Sample 1 oil @ 10kkms
TAN - 3.4
TBN - 8.0
Sample 2 oil @ 51kkms
TAN - 7.2
TBN - 2.6
Sample 3 oil @ 65kkms
TAN - 7.2
TBN - 2.0
Sample 4 oil @ 84kkms
TAN - 5.0
TBN - 2.1
Sample 5 oil @103kkms
TAN - 6.9
TBN - 2.4
We were tempted to change the oil at Sample 2 but the TAN and not the TBN reading at Sample 3 convinced us to let it live. This decision was justified as you can see by the later samples. We established an on-going OC interval of 100kkms - and averaged a 96kkms OC interval actual )
This engine has since reached almost 1mkkms ( 620000 miles ) and is about to be sold. It has had an average oil consumption of 1ltr/6.3kkms during its life to date
Example 2
Truck B
At 12/5/00 - Engine at 385kkms ( average oil temp 98C )
Sample 1 oil @ 86kkms
TAN - 8.5
TBN - 0.1
Sample 2 oil @ 94kkms
TAN - 9.1
TBN - 2.0
After Sample 1 we quickly carried out another UOA ( Sample 2 ) and even though the TBN had "restored" itself we drained the oil based on the TAN which had gone above our 75% of VOA based TBN limit. The TBN was still at our lower limit for survival
At 9/19/01- Engine at 561kkms
Sample 1 oil @ 88kkms
TAN - 6.1
TBN - 0.5
Sample 2 oil @ 92kkms
TAN - 6.8
TBN - 0.5
We elected to retain the oil based on the "suspect" TBN's and based on the relatively stable TAN readings
This vehicle was disposed of a year ago at 1mkkms without any "whole of life" engine issues at all and its oil consumption then had averaged 1ltr/6kkms ( 1 litre/3000 miles )
An oil and filter change on these vehicles costs $A400+ for oil ( Delvac 1 ) and $A100 for filters ( Donaldson ELF3998 ) which stay in place for the 100kkms OC cycle. We clean the Mann-Hummel centrifuge at every second OC. Add labour and the cost of an OC is about $A600+ plus down time!
So I believe in the end that it is all a case of interpretation and for most users on this Board as stated earlier the TBN result has more street credibility. This is probably based on "past practice" alone and more Labs may move to the TAN result alone in the future
Professional users need to use professional techniques at all times and I am sure most already do
It is great to know that so much Professional expertise exists on this Board
Regards
at least this discussion has shown some healthy viewpoints and raised all of our knowledge levels
Terry - I agree that both TBN and TAN results are desirable. I suppose you can get what you are prepared to pay for - even if the recipient may not fully understand the results. For the average user on here the TBN result is the best known - even both of them! But even the change from one to another TBN determination alone caused a bit of shock reaction here
ExxonMobil are not stupid and their move to TAN alone was probably a well balanced commercial and certainly a sincere technical decision. Their Engineers confirm this
Regarding fuel - Australia had high sulphur levels until about three years ago. At present they are now the same as in NA. Our heavy diesels use the Euro 3 & Californian emission standards. Our cars are also subject to emission legislation based on both Euro and NA standards
From my viewpoint please note the following examples in the use of TAN & TBN ( all Delvac 1 5w-40 - TBN to D4739):
Example 1
Truck A
At 9/5/00 - Engine at 126kkms ( average oil temp 103C )
Sample 1 oil @ 10kkms
TAN - 3.4
TBN - 8.0
Sample 2 oil @ 51kkms
TAN - 7.2
TBN - 2.6
Sample 3 oil @ 65kkms
TAN - 7.2
TBN - 2.0
Sample 4 oil @ 84kkms
TAN - 5.0
TBN - 2.1
Sample 5 oil @103kkms
TAN - 6.9
TBN - 2.4
We were tempted to change the oil at Sample 2 but the TAN and not the TBN reading at Sample 3 convinced us to let it live. This decision was justified as you can see by the later samples. We established an on-going OC interval of 100kkms - and averaged a 96kkms OC interval actual )
This engine has since reached almost 1mkkms ( 620000 miles ) and is about to be sold. It has had an average oil consumption of 1ltr/6.3kkms during its life to date
Example 2
Truck B
At 12/5/00 - Engine at 385kkms ( average oil temp 98C )
Sample 1 oil @ 86kkms
TAN - 8.5
TBN - 0.1
Sample 2 oil @ 94kkms
TAN - 9.1
TBN - 2.0
After Sample 1 we quickly carried out another UOA ( Sample 2 ) and even though the TBN had "restored" itself we drained the oil based on the TAN which had gone above our 75% of VOA based TBN limit. The TBN was still at our lower limit for survival
At 9/19/01- Engine at 561kkms
Sample 1 oil @ 88kkms
TAN - 6.1
TBN - 0.5
Sample 2 oil @ 92kkms
TAN - 6.8
TBN - 0.5
We elected to retain the oil based on the "suspect" TBN's and based on the relatively stable TAN readings
This vehicle was disposed of a year ago at 1mkkms without any "whole of life" engine issues at all and its oil consumption then had averaged 1ltr/6kkms ( 1 litre/3000 miles )
An oil and filter change on these vehicles costs $A400+ for oil ( Delvac 1 ) and $A100 for filters ( Donaldson ELF3998 ) which stay in place for the 100kkms OC cycle. We clean the Mann-Hummel centrifuge at every second OC. Add labour and the cost of an OC is about $A600+ plus down time!
So I believe in the end that it is all a case of interpretation and for most users on this Board as stated earlier the TBN result has more street credibility. This is probably based on "past practice" alone and more Labs may move to the TAN result alone in the future
Professional users need to use professional techniques at all times and I am sure most already do
It is great to know that so much Professional expertise exists on this Board
Regards