I've noted through several threads recently a number of disagreements about whether or not UOA results may be skewed when new oil cleans up wear metal containing deposits in the engine. I suppose this might happen either because the new oil is not exhausted like the old, or because it's just better at cleaning. Noting the disagreement on this issue, I decided to post this blurb I found while reading a Royal Purple PDS.
Originally Posted By: From the RP PDS
Note: Engine oil’s solvency cleans wear metals and deposits left by previous oils. These wear metals and deposits can cause abnormally high values on used oil analysis until the engine is clean.
For those who'd like to go direct to the source, click here.
I do not profess to know whether or not this is correct. Offered simply for consideration and comment as desired.
Originally Posted By: From the RP PDS
Note: Engine oil’s solvency cleans wear metals and deposits left by previous oils. These wear metals and deposits can cause abnormally high values on used oil analysis until the engine is clean.
For those who'd like to go direct to the source, click here.
I do not profess to know whether or not this is correct. Offered simply for consideration and comment as desired.