Originally Posted By: Gokhan
It's not the magnesium that corrodes the lead and some other metals. It's magnesium's inability to keep TAN down if calcium is depleted. Therefore, you may have a strong TBN but TAN may have gone off the roof if calcium is depleted. If GC has plenty of calcium and has a proven record, it's OK.
Where did you discover that Calcium-based additives are better at keeping TAN down?
Interesting blurb from PQIA:
"Although magnesium sulfonate is more expensive than calcium sulfonate, some formulators reportedly prefer its use due to what they feel is improved rust production seen with magnesium sulfonates as compared to calcium sulfonate in diesel engines. Because of this, whereas magnesium can be seen in the spectrographic analysis of diesel engine oils, today it is fairly uncommon to see it at any meaningful level in passenger car engine oil."
http://www.pqiamerica.com/magnesium.htm
It sounds opposite of what you are proposing.
It's not the magnesium that corrodes the lead and some other metals. It's magnesium's inability to keep TAN down if calcium is depleted. Therefore, you may have a strong TBN but TAN may have gone off the roof if calcium is depleted. If GC has plenty of calcium and has a proven record, it's OK.
Where did you discover that Calcium-based additives are better at keeping TAN down?
Interesting blurb from PQIA:
"Although magnesium sulfonate is more expensive than calcium sulfonate, some formulators reportedly prefer its use due to what they feel is improved rust production seen with magnesium sulfonates as compared to calcium sulfonate in diesel engines. Because of this, whereas magnesium can be seen in the spectrographic analysis of diesel engine oils, today it is fairly uncommon to see it at any meaningful level in passenger car engine oil."
http://www.pqiamerica.com/magnesium.htm
It sounds opposite of what you are proposing.
Last edited: